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L'ordinamento è un modo per disporre gli elementi di una lista o di un array in un determinato ordine. L'ordine può essere crescente o decrescente. IL numerico E lessicografico L'ordine (alfabetico) è un ordine ampiamente utilizzato.

In questa sezione impareremo come ordinare l'array In Giava In ascendente E discendente ordinare utilizzando il ordinare() metodo e senza utilizzare il metodo sort() . Insieme a questo, impareremo anche come ordinare il sottoarray In Giava .

ordina l'arraylist in Java

Ordina la matrice in ordine crescente

IL ordine ascendente dispone gli elementi dal più basso al più alto. È anche noto come ordine naturale O ordine numerico . Possiamo eseguire l'ordinamento nei seguenti modi:

• Utilizzando il metodo sort()
• Senza utilizzare il metodo
  • Utilizzando il ciclo for
  • Utilizzando il metodo definito dall'utente

Utilizzando il metodo sort()

A Giava, Array è la classe definita injava.utilpacchetto che fornisce ordinare() metodo per ordinare un array in ordine crescente. Utilizza Algoritmo Quicksort a doppio pivot per l'ordinamento. La sua complessità è O(n log(n)) . È un statico metodo che analizza un vettore come parametro e non restituisce nulla. Possiamo invocarlo direttamente utilizzando il nome della classe. Accetta un array di tipo int, float, double, long, char, byte.

Sintassi:

 public static void sort(int[] a) 

Dove UN è un array che deve essere breve.

Nota: come la classe Arrays, anche la classe Collections fornisce il metodo sort() per ordinare l'array. Ma c'è una differenza tra loro. Il metodo sort() della classe Arrays funziona per il tipo primitivo mentre il metodo sort() della classe Collections funziona per le raccolte di oggetti, come LinkedList, ArrayList, ecc.

Ordiniamo un array utilizzando il metodo sort() della classe Arrays.

Nel seguente programma abbiamo definito un array di tipo intero. Successivamente, abbiamo invocato il metodo sort() della classe Arrays e abbiamo analizzato l'array per essere ordinato. Per stampare l'array ordinato, abbiamo utilizzato il ciclo for.

SortArrayEsempio1.java

 import java.util.Arrays; public class SortArrayExample1 { public static void main(String[] args) { //defining an array of integer type int [] array = new int [] {90, 23, 5, 109, 12, 22, 67, 34}; //invoking sort() method of the Arrays class Arrays.sort(array); System.out.println(&apos;Elements of array sorted in ascending order: &apos;); //prints array using the for loop for (int i = 0; i <array.length; i++) { system.out.println(array[i]); } < pre> <p> <strong>Output:</strong> </p> <pre> Array elements in ascending order: 5 12 22 23 34 67 90 109 </pre> <p>In the above program, we can also use the toSting() method of the Arrays class to print the array, as shown in the following statement. It returns a string representation of the specified array.</p> <pre> System.out.printf(Arrays.toString(array)); </pre> <h3>Without Using the Method</h3> <h3>Using the for Loop</h3> <p>In the following example, we have initialized an array of integer type and sort the array in ascending order.</p> <p> <strong>SortArrayExample2.java</strong> </p> <pre> public class SortArrayExample2 { public static void main(String[] args) { //creating an instance of an array int[] arr = new int[] {78, 34, 1, 3, 90, 34, -1, -4, 6, 55, 20, -65}; System.out.println(&apos;Array elements after sorting:&apos;); //sorting logic for (int i = 0; i <arr.length; i++) { for (int j="i" + 1; arr[j]) tmp="arr[i];" arr[i]="arr[j];" arr[j]="tmp;" } prints the sorted element of array system.out.println(arr[i]); < pre> <p> <strong>Output:</strong> </p> <pre> Array elements after sorting: -65 -4 -1 1 3 6 20 34 34 55 78 90 </pre> <h3>Using the User Defined Method</h3> <p>In the following example, we have defined a method named <strong>sortArray()</strong> that contains the logic to sort an array in natural order.</p> <p> <strong>SortArrayExample3.java</strong> </p> <pre> public class SortArrayExample3 { public static void main(String[] args) { int i; //initializing an array int array[] = {12, 45, 1, -1, 0, 4, 56, 23, 89, -21, 56, 27}; System.out.print(&apos;Array elements before sorting: 
&apos;); for(i = 0; i <array.length; i++) system.out.println(array[i]); invoking user defined method sortarray(array, array.length); system.out.print('array elements after sorting: 
'); accessing of the sorted array for(i="0;" i <array.length; { } to sort an in ascending order private static void sortarray(int array[], int n) for (int <n; j="i;" a="array[i];" while ((j> 0) &amp;&amp; (array[j-1] &gt; a)) //returns true when both conditions are true { array[j] = array[j-1]; j--; } array[j] = a; } } } </array.length;></pre> <p> <strong>Output:</strong> </p> <pre> Array elements before sorting: 12 45 1 -1 0 4 56 23 89 -21 56 27 Array elements after sorting: -21 -1 0 1 4 12 23 27 45 56 56 89 </pre> <h2>Sort Array in Descending Order</h2> <p>The <strong>descending order</strong> arranges the elements in the highest to lowest order. We can perform sorting in the following ways:</p> <ul> <li>Using the <strong>reverseOrder()</strong> Method</li> <li>Without using the method <ul> <li>Using the <strong>for</strong> Loop</li> <li>Using the <strong>User Defined</strong> Method</li> </ul></li> </ul> <h3>Using the reverseOrder() Method</h3> <p> <a href="/java-collections-class">Java <strong>Collections</strong> class</a> provides the <strong>reverseOrder()</strong> method to sort the array in reverse-lexicographic order. It is a static method, so we can invoke it directly by using the class name. It does not parse any parameter. It returns a <strong>comparator</strong> that imposes the reverse of the natural ordering (ascending order).</p> <p>It means that the array sorts elements in the ascending order by using the sort() method, after that the reverseOrder() method reverses the natural ordering, and we get the sorted array in descending order.</p> <p> <strong>Syntax:</strong> </p> <pre> public static Comparator reverseOrder() </pre> <p>Suppose, a[] is an array to be sort in the descending order. We will use the reverseOrder() method in the following way:</p> <pre> Arrays.sort(a, Collections.reverseOrder()); </pre> <p>Let&apos;s sorts an array in the descending order.</p> <p>In the following program, a point to be noticed that we have defined an array as <strong>Integer</strong> . Because the reverseOrder() method does not work for the primitive data type.</p> <p> <strong>SortArrayExample4.java</strong> </p> <pre> import java.util.Arrays; import java.util.Collections; public class SortArrayExample4 { public static void main(String[] args) { Integer [] array = {23, -9, 78, 102, 4, 0, -1, 11, 6, 110, 205}; // sorts array[] in descending order Arrays.sort(array, Collections.reverseOrder()); System.out.println(&apos;Array elements in descending order: &apos; +Arrays.toString(array)); } } </pre> <p> <strong>Output:</strong> </p> <pre> Array elements in descending order: [205, 110, 102, 78, 23, 11, 6, 4, 0, -1, -9] </pre> <p>Let&apos;s see another program that sorts array elements in alphabetical order.</p> <p> <strong>SortArrayExample5.java</strong> </p> <pre> import java.util.Arrays; import java.util.Collections; public class SortArrayExample5 { public static void main(String[] args) { String [] strarray = {&apos;Mango&apos;, &apos;Apple&apos;, &apos;Grapes&apos;, &apos;Papaya&apos;, &apos;Pineapple&apos;, &apos;Banana&apos;, &apos;Orange&apos;}; // sorts array[] in descending order Arrays.sort(strarray, Collections.reverseOrder()); System.out.println(&apos;Array elements in descending order: &apos; +Arrays.toString(strarray)); } } </pre> <p> <strong>Output:</strong> </p> <pre> Array elements in descending order: [Papaya, Pineapple, Orange, Mango, Grapes, Banana, Apple] </pre> <h3>Without Using the Method</h3> <h3>Using the for Loop</h3> <p>In the following example, we have initialized an integer array and perform sorting in descending order.</p> <p> <strong>SortArrayExample6.java</strong> </p> <pre> public class SortArrayExample6 { public static void main(String[] args) { int temp; //initializing an array int a[]={12,5,56,-2,32,2,-26,9,43,94,-78}; for (int i = 0; i <a.length; i++) { for (int j="i" + 1; < a.length; j++) if (a[i] a[j]) temp="a[i];" a[i]="a[j];" a[j]="temp;" } system.out.println('array elements in descending order:'); accessing element of the array i="0;" - system.out.println(a[i]); pre> <p> <strong>Output:</strong> </p> <pre> Array elements in descending order: 94 56 43 32 12 9 5 2 -2 -26 -78 </pre> <h3>Using the User Defined Method</h3> <p> <strong>SortArrayExample7.java</strong> </p> <pre> import java.util.Scanner; public class SortArrayExample7 { public static void main(String[] args) { int n, temp; Scanner s = new Scanner(System.in); System.out.print(&apos;Enter the number of elements: &apos;); n = s.nextInt(); int a[] = new int[n]; System.out.println(&apos;Enter the elements of the array: &apos;); for (int i = 0; i <n; i++) { a[i]="s.nextInt();" } for (int i="0;" < n; j="i" + 1; j++) if (a[i] a[j]) temp="a[i];" a[j]="temp;" system.out.println('array elements in descending order:'); n - system.out.println(a[i]); system.out.print(a[n 1]); pre> <p> <strong>Output:</strong> </p> <pre> Enter the number of elements: 7 Enter the elements of the array: 12 5 56 -2 32 2 -26 Array elements in descending order: 56 32 12 5 2 -2 -26 </pre> <h2>How to Sort Subarray</h2> <p>An array derived from the array is known as <strong>subarray</strong> . Suppose, <strong>a[]</strong> is an array having the elements [12, 90, 34, 2, 45, 3, 22, 18, 5, 78] and we want to sort array elements from 34 to 18. It will sort the subarray <strong>[34, 2, 45, 3, 22, 18]</strong> and keep the other elements as it is.</p> <p>To sort the subarray, the Arrays class provides the static method named <strong>sort()</strong> . It sorts the specified range of the array into ascending order. We can also sort the array of type <strong>long, double, float, char, byte,</strong> etc.</p> <p> <strong>Syntax:</strong> </p> <pre> public static void sort(int[] a, int fromIndex, int toIndex) </pre> <p>The method parses the following three parameters:</p> <ul> <tr><td>a:</td> An array to be sort. </tr><tr><td>fromIndex:</td> The index of the first element of the subarray. It participates in the sorting. </tr><tr><td>toIndex:</td> The index of the last element of the subarray. It does not participate in the sorting. </tr></ul> <p>If formIndex is equal to the toIndex, the range to be sorted is empty. It throws IllegalArgumentException if <strong>fomIndex is greater than toIndex</strong> . It also throws ArrayIndexOutOfBoundsException if <strong>fromIndex a.length</strong> .</p> <p>Let&apos;s sort a subarray through a Java program.</p> <p> <strong>SortSubarrayExample.java</strong> </p> <pre> import java.util.Arrays; public class SortSubarrayExample { public static void main(String[] args) { //defining an array int[] a = {12, 90, 34, 2, 45, 3, 22, 18, 5, 78}; // sorts subarray form index 2 to 7 Arrays.sort(a, 2, 7); //prints array using the for loop for (int i = 0; i <a.length; i++) { system.out.println(a[i]); } < pre> <p> <strong>Output:</strong> </p> <pre> Sorted Subarray: 12 90 2 3 22 34 45 18 5 78 </pre> <hr></a.length;></pre></n;></pre></a.length;></pre></arr.length;></pre></array.length;>

Nel programma sopra, possiamo anche utilizzare il metodo toSting() della classe Arrays per stampare l'array, come mostrato nella seguente istruzione. Restituisce una rappresentazione di stringa dell'array specificato.

 System.out.printf(Arrays.toString(array)); 

Senza usare il metodo

Utilizzando il ciclo for

Nell'esempio seguente, abbiamo inizializzato un array di tipo intero e ordinato l'array in ordine crescente.

SortArrayExample2.java

 public class SortArrayExample2 { public static void main(String[] args) { //creating an instance of an array int[] arr = new int[] {78, 34, 1, 3, 90, 34, -1, -4, 6, 55, 20, -65}; System.out.println(&apos;Array elements after sorting:&apos;); //sorting logic for (int i = 0; i <arr.length; i++) { for (int j="i" + 1; arr[j]) tmp="arr[i];" arr[i]="arr[j];" arr[j]="tmp;" } prints the sorted element of array system.out.println(arr[i]); < pre> <p> <strong>Output:</strong> </p> <pre> Array elements after sorting: -65 -4 -1 1 3 6 20 34 34 55 78 90 </pre> <h3>Using the User Defined Method</h3> <p>In the following example, we have defined a method named <strong>sortArray()</strong> that contains the logic to sort an array in natural order.</p> <p> <strong>SortArrayExample3.java</strong> </p> <pre> public class SortArrayExample3 { public static void main(String[] args) { int i; //initializing an array int array[] = {12, 45, 1, -1, 0, 4, 56, 23, 89, -21, 56, 27}; System.out.print(&apos;Array elements before sorting: 
&apos;); for(i = 0; i <array.length; i++) system.out.println(array[i]); invoking user defined method sortarray(array, array.length); system.out.print(\'array elements after sorting: 
\'); accessing of the sorted array for(i="0;" i <array.length; { } to sort an in ascending order private static void sortarray(int array[], int n) for (int <n; j="i;" a="array[i];" while ((j> 0) &amp;&amp; (array[j-1] &gt; a)) //returns true when both conditions are true { array[j] = array[j-1]; j--; } array[j] = a; } } } </array.length;></pre> <p> <strong>Output:</strong> </p> <pre> Array elements before sorting: 12 45 1 -1 0 4 56 23 89 -21 56 27 Array elements after sorting: -21 -1 0 1 4 12 23 27 45 56 56 89 </pre> <h2>Sort Array in Descending Order</h2> <p>The <strong>descending order</strong> arranges the elements in the highest to lowest order. We can perform sorting in the following ways:</p> <ul> <li>Using the <strong>reverseOrder()</strong> Method</li> <li>Without using the method <ul> <li>Using the <strong>for</strong> Loop</li> <li>Using the <strong>User Defined</strong> Method</li> </ul></li> </ul> <h3>Using the reverseOrder() Method</h3> <p> <a href="/java-collections-class">Java <strong>Collections</strong> class</a> provides the <strong>reverseOrder()</strong> method to sort the array in reverse-lexicographic order. It is a static method, so we can invoke it directly by using the class name. It does not parse any parameter. It returns a <strong>comparator</strong> that imposes the reverse of the natural ordering (ascending order).</p> <p>It means that the array sorts elements in the ascending order by using the sort() method, after that the reverseOrder() method reverses the natural ordering, and we get the sorted array in descending order.</p> <p> <strong>Syntax:</strong> </p> <pre> public static Comparator reverseOrder() </pre> <p>Suppose, a[] is an array to be sort in the descending order. We will use the reverseOrder() method in the following way:</p> <pre> Arrays.sort(a, Collections.reverseOrder()); </pre> <p>Let&apos;s sorts an array in the descending order.</p> <p>In the following program, a point to be noticed that we have defined an array as <strong>Integer</strong> . Because the reverseOrder() method does not work for the primitive data type.</p> <p> <strong>SortArrayExample4.java</strong> </p> <pre> import java.util.Arrays; import java.util.Collections; public class SortArrayExample4 { public static void main(String[] args) { Integer [] array = {23, -9, 78, 102, 4, 0, -1, 11, 6, 110, 205}; // sorts array[] in descending order Arrays.sort(array, Collections.reverseOrder()); System.out.println(&apos;Array elements in descending order: &apos; +Arrays.toString(array)); } } </pre> <p> <strong>Output:</strong> </p> <pre> Array elements in descending order: [205, 110, 102, 78, 23, 11, 6, 4, 0, -1, -9] </pre> <p>Let&apos;s see another program that sorts array elements in alphabetical order.</p> <p> <strong>SortArrayExample5.java</strong> </p> <pre> import java.util.Arrays; import java.util.Collections; public class SortArrayExample5 { public static void main(String[] args) { String [] strarray = {&apos;Mango&apos;, &apos;Apple&apos;, &apos;Grapes&apos;, &apos;Papaya&apos;, &apos;Pineapple&apos;, &apos;Banana&apos;, &apos;Orange&apos;}; // sorts array[] in descending order Arrays.sort(strarray, Collections.reverseOrder()); System.out.println(&apos;Array elements in descending order: &apos; +Arrays.toString(strarray)); } } </pre> <p> <strong>Output:</strong> </p> <pre> Array elements in descending order: [Papaya, Pineapple, Orange, Mango, Grapes, Banana, Apple] </pre> <h3>Without Using the Method</h3> <h3>Using the for Loop</h3> <p>In the following example, we have initialized an integer array and perform sorting in descending order.</p> <p> <strong>SortArrayExample6.java</strong> </p> <pre> public class SortArrayExample6 { public static void main(String[] args) { int temp; //initializing an array int a[]={12,5,56,-2,32,2,-26,9,43,94,-78}; for (int i = 0; i <a.length; i++) { for (int j="i" + 1; < a.length; j++) if (a[i] a[j]) temp="a[i];" a[i]="a[j];" a[j]="temp;" } system.out.println(\'array elements in descending order:\'); accessing element of the array i="0;" - system.out.println(a[i]); pre> <p> <strong>Output:</strong> </p> <pre> Array elements in descending order: 94 56 43 32 12 9 5 2 -2 -26 -78 </pre> <h3>Using the User Defined Method</h3> <p> <strong>SortArrayExample7.java</strong> </p> <pre> import java.util.Scanner; public class SortArrayExample7 { public static void main(String[] args) { int n, temp; Scanner s = new Scanner(System.in); System.out.print(&apos;Enter the number of elements: &apos;); n = s.nextInt(); int a[] = new int[n]; System.out.println(&apos;Enter the elements of the array: &apos;); for (int i = 0; i <n; i++) { a[i]="s.nextInt();" } for (int i="0;" < n; j="i" + 1; j++) if (a[i] a[j]) temp="a[i];" a[j]="temp;" system.out.println(\'array elements in descending order:\'); n - system.out.println(a[i]); system.out.print(a[n 1]); pre> <p> <strong>Output:</strong> </p> <pre> Enter the number of elements: 7 Enter the elements of the array: 12 5 56 -2 32 2 -26 Array elements in descending order: 56 32 12 5 2 -2 -26 </pre> <h2>How to Sort Subarray</h2> <p>An array derived from the array is known as <strong>subarray</strong> . Suppose, <strong>a[]</strong> is an array having the elements [12, 90, 34, 2, 45, 3, 22, 18, 5, 78] and we want to sort array elements from 34 to 18. It will sort the subarray <strong>[34, 2, 45, 3, 22, 18]</strong> and keep the other elements as it is.</p> <p>To sort the subarray, the Arrays class provides the static method named <strong>sort()</strong> . It sorts the specified range of the array into ascending order. We can also sort the array of type <strong>long, double, float, char, byte,</strong> etc.</p> <p> <strong>Syntax:</strong> </p> <pre> public static void sort(int[] a, int fromIndex, int toIndex) </pre> <p>The method parses the following three parameters:</p> <ul> <tr><td>a:</td> An array to be sort. </tr><tr><td>fromIndex:</td> The index of the first element of the subarray. It participates in the sorting. </tr><tr><td>toIndex:</td> The index of the last element of the subarray. It does not participate in the sorting. </tr></ul> <p>If formIndex is equal to the toIndex, the range to be sorted is empty. It throws IllegalArgumentException if <strong>fomIndex is greater than toIndex</strong> . It also throws ArrayIndexOutOfBoundsException if <strong>fromIndex a.length</strong> .</p> <p>Let&apos;s sort a subarray through a Java program.</p> <p> <strong>SortSubarrayExample.java</strong> </p> <pre> import java.util.Arrays; public class SortSubarrayExample { public static void main(String[] args) { //defining an array int[] a = {12, 90, 34, 2, 45, 3, 22, 18, 5, 78}; // sorts subarray form index 2 to 7 Arrays.sort(a, 2, 7); //prints array using the for loop for (int i = 0; i <a.length; i++) { system.out.println(a[i]); } < pre> <p> <strong>Output:</strong> </p> <pre> Sorted Subarray: 12 90 2 3 22 34 45 18 5 78 </pre> <hr></a.length;></pre></n;></pre></a.length;></pre></arr.length;>

Utilizzando il metodo definito dall'utente

Nell'esempio seguente, abbiamo definito un metodo denominato sortArray() che contiene la logica per ordinare un array in ordine naturale.

xd xd significato

SortArrayEsempio3.java

 public class SortArrayExample3 { public static void main(String[] args) { int i; //initializing an array int array[] = {12, 45, 1, -1, 0, 4, 56, 23, 89, -21, 56, 27}; System.out.print('Array elements before sorting: 
&apos;); for(i = 0; i <array.length; i++) system.out.println(array[i]); invoking user defined method sortarray(array, array.length); system.out.print(\'array elements after sorting: 
\'); accessing of the sorted array for(i="0;" i <array.length; { } to sort an in ascending order private static void sortarray(int array[], int n) for (int <n; j="i;" a="array[i];" while ((j> 0) &amp;&amp; (array[j-1] &gt; a)) //returns true when both conditions are true { array[j] = array[j-1]; j--; } array[j] = a; } } } </array.length;>

Produzione:

 Array elements before sorting: 12 45 1 -1 0 4 56 23 89 -21 56 27 Array elements after sorting: -21 -1 0 1 4 12 23 27 45 56 56 89 

Ordina la matrice in ordine decrescente

IL ordine decrescente dispone gli elementi dal più alto al più basso. Possiamo eseguire l'ordinamento nei seguenti modi:

• Usando il ordine inverso() Metodo
• Senza utilizzare il metodo
  • Usando il per Ciclo continuo
  • Usando il Definito dall'utente Metodo

Utilizzando il metodo reverseOrder()

Giava Collezioni classe fornisce il ordine inverso() metodo per ordinare l'array in ordine lessicografico inverso. È un metodo statico, quindi possiamo invocarlo direttamente utilizzando il nome della classe. Non analizza alcun parametro. Restituisce a comparatore che impone l'inverso dell'ordinamento naturale (ordine ascendente).

Significa che l'array ordina gli elementi in ordine crescente utilizzando il metodo sort(), dopodiché il metodo reverseOrder() inverte l'ordinamento naturale e otteniamo l'array ordinato in ordine decrescente.

Sintassi:

fattoriale in Java

 public static Comparator reverseOrder() 

Supponiamo che a[] sia un array da ordinare in ordine decrescente. Utilizzeremo il metodo reverseOrder() nel modo seguente:

 Arrays.sort(a, Collections.reverseOrder()); 

Ordiniamo un array in ordine decrescente.

Nel seguente programma, un punto da notare è che abbiamo definito un array come Numero intero . Perché il metodo reverseOrder() non funziona per il tipo di dati primitivo.

SortArrayExample4.java

scan.nextstring java

 import java.util.Arrays; import java.util.Collections; public class SortArrayExample4 { public static void main(String[] args) { Integer [] array = {23, -9, 78, 102, 4, 0, -1, 11, 6, 110, 205}; // sorts array[] in descending order Arrays.sort(array, Collections.reverseOrder()); System.out.println('Array elements in descending order: ' +Arrays.toString(array)); } } 

Produzione:

 Array elements in descending order: [205, 110, 102, 78, 23, 11, 6, 4, 0, -1, -9] 

Vediamo un altro programma che ordina gli elementi dell'array in ordine alfabetico.

SortArrayExample5.java

 import java.util.Arrays; import java.util.Collections; public class SortArrayExample5 { public static void main(String[] args) { String [] strarray = {'Mango', 'Apple', 'Grapes', 'Papaya', 'Pineapple', 'Banana', 'Orange'}; // sorts array[] in descending order Arrays.sort(strarray, Collections.reverseOrder()); System.out.println('Array elements in descending order: ' +Arrays.toString(strarray)); } } 

Produzione:

 Array elements in descending order: [Papaya, Pineapple, Orange, Mango, Grapes, Banana, Apple] 

Senza usare il metodo

Utilizzando il ciclo for

Nell'esempio seguente, abbiamo inizializzato un array di numeri interi ed eseguito l'ordinamento in ordine decrescente.

SortArrayEsempio6.java

 public class SortArrayExample6 { public static void main(String[] args) { int temp; //initializing an array int a[]={12,5,56,-2,32,2,-26,9,43,94,-78}; for (int i = 0; i <a.length; i++) { for (int j="i" + 1; < a.length; j++) if (a[i] a[j]) temp="a[i];" a[i]="a[j];" a[j]="temp;" } system.out.println(\'array elements in descending order:\'); accessing element of the array i="0;" - system.out.println(a[i]); pre> <p> <strong>Output:</strong> </p> <pre> Array elements in descending order: 94 56 43 32 12 9 5 2 -2 -26 -78 </pre> <h3>Using the User Defined Method</h3> <p> <strong>SortArrayExample7.java</strong> </p> <pre> import java.util.Scanner; public class SortArrayExample7 { public static void main(String[] args) { int n, temp; Scanner s = new Scanner(System.in); System.out.print(&apos;Enter the number of elements: &apos;); n = s.nextInt(); int a[] = new int[n]; System.out.println(&apos;Enter the elements of the array: &apos;); for (int i = 0; i <n; i++) { a[i]="s.nextInt();" } for (int i="0;" < n; j="i" + 1; j++) if (a[i] a[j]) temp="a[i];" a[j]="temp;" system.out.println(\'array elements in descending order:\'); n - system.out.println(a[i]); system.out.print(a[n 1]); pre> <p> <strong>Output:</strong> </p> <pre> Enter the number of elements: 7 Enter the elements of the array: 12 5 56 -2 32 2 -26 Array elements in descending order: 56 32 12 5 2 -2 -26 </pre> <h2>How to Sort Subarray</h2> <p>An array derived from the array is known as <strong>subarray</strong> . Suppose, <strong>a[]</strong> is an array having the elements [12, 90, 34, 2, 45, 3, 22, 18, 5, 78] and we want to sort array elements from 34 to 18. It will sort the subarray <strong>[34, 2, 45, 3, 22, 18]</strong> and keep the other elements as it is.</p> <p>To sort the subarray, the Arrays class provides the static method named <strong>sort()</strong> . It sorts the specified range of the array into ascending order. We can also sort the array of type <strong>long, double, float, char, byte,</strong> etc.</p> <p> <strong>Syntax:</strong> </p> <pre> public static void sort(int[] a, int fromIndex, int toIndex) </pre> <p>The method parses the following three parameters:</p> <ul> <tr><td>a:</td> An array to be sort. </tr><tr><td>fromIndex:</td> The index of the first element of the subarray. It participates in the sorting. </tr><tr><td>toIndex:</td> The index of the last element of the subarray. It does not participate in the sorting. </tr></ul> <p>If formIndex is equal to the toIndex, the range to be sorted is empty. It throws IllegalArgumentException if <strong>fomIndex is greater than toIndex</strong> . It also throws ArrayIndexOutOfBoundsException if <strong>fromIndex a.length</strong> .</p> <p>Let&apos;s sort a subarray through a Java program.</p> <p> <strong>SortSubarrayExample.java</strong> </p> <pre> import java.util.Arrays; public class SortSubarrayExample { public static void main(String[] args) { //defining an array int[] a = {12, 90, 34, 2, 45, 3, 22, 18, 5, 78}; // sorts subarray form index 2 to 7 Arrays.sort(a, 2, 7); //prints array using the for loop for (int i = 0; i <a.length; i++) { system.out.println(a[i]); } < pre> <p> <strong>Output:</strong> </p> <pre> Sorted Subarray: 12 90 2 3 22 34 45 18 5 78 </pre> <hr></a.length;></pre></n;></pre></a.length;>

Utilizzando il metodo definito dall'utente

SortArrayEsempio7.java

 import java.util.Scanner; public class SortArrayExample7 { public static void main(String[] args) { int n, temp; Scanner s = new Scanner(System.in); System.out.print(&apos;Enter the number of elements: &apos;); n = s.nextInt(); int a[] = new int[n]; System.out.println(&apos;Enter the elements of the array: &apos;); for (int i = 0; i <n; i++) { a[i]="s.nextInt();" } for (int i="0;" < n; j="i" + 1; j++) if (a[i] a[j]) temp="a[i];" a[j]="temp;" system.out.println(\'array elements in descending order:\'); n - system.out.println(a[i]); system.out.print(a[n 1]); pre> <p> <strong>Output:</strong> </p> <pre> Enter the number of elements: 7 Enter the elements of the array: 12 5 56 -2 32 2 -26 Array elements in descending order: 56 32 12 5 2 -2 -26 </pre> <h2>How to Sort Subarray</h2> <p>An array derived from the array is known as <strong>subarray</strong> . Suppose, <strong>a[]</strong> is an array having the elements [12, 90, 34, 2, 45, 3, 22, 18, 5, 78] and we want to sort array elements from 34 to 18. It will sort the subarray <strong>[34, 2, 45, 3, 22, 18]</strong> and keep the other elements as it is.</p> <p>To sort the subarray, the Arrays class provides the static method named <strong>sort()</strong> . It sorts the specified range of the array into ascending order. We can also sort the array of type <strong>long, double, float, char, byte,</strong> etc.</p> <p> <strong>Syntax:</strong> </p> <pre> public static void sort(int[] a, int fromIndex, int toIndex) </pre> <p>The method parses the following three parameters:</p> <ul> <tr><td>a:</td> An array to be sort. </tr><tr><td>fromIndex:</td> The index of the first element of the subarray. It participates in the sorting. </tr><tr><td>toIndex:</td> The index of the last element of the subarray. It does not participate in the sorting. </tr></ul> <p>If formIndex is equal to the toIndex, the range to be sorted is empty. It throws IllegalArgumentException if <strong>fomIndex is greater than toIndex</strong> . It also throws ArrayIndexOutOfBoundsException if <strong>fromIndex a.length</strong> .</p> <p>Let&apos;s sort a subarray through a Java program.</p> <p> <strong>SortSubarrayExample.java</strong> </p> <pre> import java.util.Arrays; public class SortSubarrayExample { public static void main(String[] args) { //defining an array int[] a = {12, 90, 34, 2, 45, 3, 22, 18, 5, 78}; // sorts subarray form index 2 to 7 Arrays.sort(a, 2, 7); //prints array using the for loop for (int i = 0; i <a.length; i++) { system.out.println(a[i]); } < pre> <p> <strong>Output:</strong> </p> <pre> Sorted Subarray: 12 90 2 3 22 34 45 18 5 78 </pre> <hr></a.length;></pre></n;>

Come ordinare il sottoarray

Un array derivato dall'array è noto come sottoarray . Supponiamo, UN[] è un array avente gli elementi [12, 90, 34, 2, 45, 3, 22, 18, 5, 78] e vogliamo ordinare gli elementi dell'array da 34 a 18. Ordina il sottoarray [34, 2, 45, 3, 22, 18] e mantieni gli altri elementi così come sono.

Per ordinare il sottoarray, la classe Arrays fornisce il metodo statico denominato ordinare() . Ordina l'intervallo specificato dell'array in ordine crescente. Possiamo anche ordinare l'array di tipo lungo, doppio, float, carattere, byte, eccetera.

Sintassi:

 public static void sort(int[] a, int fromIndex, int toIndex) 

Il metodo analizza i seguenti tre parametri:

ops concetti in Java

UN:Un array da ordinare.daIndice:L'indice del primo elemento del sottoarray. Partecipa allo smistamento.all'Indice:L'indice dell'ultimo elemento del sottoarray. Non partecipa allo smistamento.

Se formIndex è uguale a toIndex, l'intervallo da ordinare è vuoto. Lancia IllegalArgumentException se fomIndex è maggiore di toIndex . Lancia anche ArrayIndexOutOfBoundsException if daIndice a.lunghezza .

Ordiniamo un sottoarray tramite un programma Java.

SortSubarrayExample.java

 import java.util.Arrays; public class SortSubarrayExample { public static void main(String[] args) { //defining an array int[] a = {12, 90, 34, 2, 45, 3, 22, 18, 5, 78}; // sorts subarray form index 2 to 7 Arrays.sort(a, 2, 7); //prints array using the for loop for (int i = 0; i <a.length; i++) { system.out.println(a[i]); } < pre> <p> <strong>Output:</strong> </p> <pre> Sorted Subarray: 12 90 2 3 22 34 45 18 5 78 </pre> <hr></a.length;>