I am trying to get an input to a matrix by placing the whole thing as in a function outside of main (), as follows:

```
void input_matrix(int row, int col){
std::vector<std::vector<int>> matrix;
for (int m=0; m<row; m++){
for (int n=0; n<col; n++){
std::cin >> matrix[m][n];
}
}
return matrix;
}
```

somehow the compiler doesn’t like me inputing the matrix here, any solutions?

Source: Windows Questions C++