how to initialize 2d vector c++ code example
Example 1: initialize 2d vector of ints c++
auto M = 4; // num of rows
auto N = 3; // num of cols in each row
auto default_value = 1; // default value of all int elements
std::vector<std::vector<int>> matrix(M, std::vector<int>(N, default_value));
Example 2: initializing 2d vector
vector<vector<int> > vec( n , vector<int> (m, 0));