#include using namespace std; int main(){ int n = 4; // number of nodes. int m = 2; // number of edges. vector edges = {{2, 3}, {4, 3}}; // the edges going from first to second. set s; for(int i = 0; i < m; i++){ s.insert(edges[i].first); // will keep value of // distinct node from which edges are going out. } cout