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Implementazione della mappa multidimensionale in C++

Multidimensionale carta geografica s vengono utilizzati quando vogliamo associare un valore a una combinazione di chiavi. La chiave può essere di qualsiasi tipo di dati, compresi quelli definiti dall'utente. Le mappe multidimensionali sono mappe annidate; ovvero, mappano una chiave su un'altra mappa, che a sua volta memorizza combinazioni di valori chiave con valori mappati corrispondenti.

Sintassi:



 // Creating a two-dimensional map: map object; // Creating an N-dimensional map: map>oggetto;>

Esempio 1:




Java Ciao mondo esempio





// C++14 code to implement two-dimensional map> > #include> using> namespace> std;> > int> main()> {> > >// Two-dimensional key> >map<>int>, map<>int>,>int>>>m;> > >// For accessing outer map> >map<>int>, map<>int>,>int>>>::iteratore itr;> > >// For accessing inner map> >map<>int>,>int>>::iteratore ptr;> > >for> (>int> i = 0; i <2; i++) {> >for> (>int> j = 0; j <2; j++) {> >m[i][j] = i + j;> >}> >}> > >for> (>int> i = 0; i <2; i++) {> >for> (>int> j = 0; j <2; j++) {> > >// Accessing through array subscript> >cout <<>'First key is '> << i> ><<>' And second key is '> << j> ><<>' And value is '> << m[i][j] << endl;> >}> >}> > >cout <<>' Now accessing map though iterator '>;> > >for> (itr = m.begin(); itr != m.end(); itr++) {> > >for> (ptr = itr->secondo.inizio(); ptr != itr->second.end(); ptr++) {> >cout <<>'First key is '> << ' And second key is ' << ' And value is ' } } }>

C#
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Produzione:

 First key is 0 And second key is 0 And value is 0 First key is 0 And second key is 1 And value is 1 First key is 1 And second key is 0 And value is 1 First key is 1 And second key is 1 And value is 2 Now accessing map though iterator First key is 0 And second key is 0 And value is 0 First key is 0 And second key is 1 And value is 1 First key is 1 And second key is 0 And value is 1 First key is 1 And second key is 1 And value is 2>

Esempio 2:

attraversamento degli ordini per corrispondenza dell'albero binario




// C++14 code to implement two-dimensional map> // and inserting value through insert()> > #include> using> namespace> std;> > int> main()> {> > >// First key type is a string> >mapint, int>>m; mapint, int>>::iterator itr; carta geografica ::iteratore ptr; m.insert(make_pair('Noob', map ())); m['Noob'].insert(make_pair(0, 5)); m.insert(make_pair('Geek', map ())); m['Geek'].insert(make_pair(1, 10)); m.insert(make_pair('Geek', map ())); m['Geek'].insert(make_pair(2, 20)); for (itr = m.begin(); itr != m.end(); itr++) { for (ptr = itr->second.begin(); ptr != itr->second.end(); ptr++) { cout<< 'First key is ' << ' And second key is ' << ' And value is ' } } }>

>

q1 q2 q3 q4

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Produzione:

 First key is Geek And second key is 1 And value is 10 First key is Geek And second key is 2 And value is 20 First key is Noob And second key is 0 And value is 5>