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How do I declare a 2d array in C++ using new
A dynamic 2D array is basically an array of pointers to arrays. Here is a diagram of a 2D array with dimenation 3 x 4.

Algorithm
Begin Declare dimension of the array. Dynamic allocate 2D array a[][] using new. Fill the array with the elements. Print the array. Clear the memory by deleting it. End
Example Code
#include <iostream>
using namespace std;
int main() {
int B = 4;
int A = 5;
int** a = new int*[B];
for(int i = 0; i < B; ++i)
a[i] = new int[A];
for(int i = 0; i < B; ++i)
for(int j = 0; j < A; ++j)
a[i][j] = i;
for(int i = 0; i < B; ++i)
for(int j = 0; j < A; ++j)
cout << a[i][j] << "\n";
for(int i = 0; i < A; ++i)
delete [] a[i];
delete [] a;
return 0;
}
Output
0 0 0 0 0 1 1 1 1 1 2 2 2 2 2 3 3 3 3 3
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