auto M = 4; // num of rowsauto N = 3; // num of cols in each rowauto default_value = 1; // default value of all int elementsstd::vector<std::vector<int>> matrix(M, std::vector<int>(N, default_value));
myVector[
Vector[0, 4, 2, 5],
Vector[1, 4, 2]
];
/*When you call for myVector[1].size() it would return 3 and [0] would return 4.
For the amount of rows (int vectors) in the 2d vector, you can just use myVector.size()
You can run this to see it in actions*/
#include<bits/stdc++.h> usingnamespacestd;
intmain(){
int n = 3;
int m = 4;
// Create a vector containing n //vectors of size m. vector<vector<int> > vec( n , vector<int> (m, 0));
for (int i = 0; i < n; i++) {
for (int j = 0; j < m; j++){
cout<< vec[i][j]<< " ";
}
cout<< "\n";
}
return0;
}