DFS of graph

// // Created by YUQIONG LI on 16/9/2018. // #include <iostream> #include <map> #include <vector> #include <stack> using std::cout; using std::map; using std::vector; using std::endl; using std::stack; map< int, vector<int> > makeGraph(){ map<int, vector<int> > m; m[0] = {1, 3}; m[1] = {3, 0, 1}; m[2] = {2}; m[3] = {0}; return m; }; int main(){ map<int, vector<int> > m = makeGraph(); vector<int> visited; stack<int> s; s.push(0); while(!s.empty()){ int curr = s.top(); if (std::find(visited.begin(), visited.end(), curr) != visited.end()){ // already visited s.pop(); continue; } cout << curr << ' '; s.pop(); visited.push_back(curr); for (auto & neighbors: m[curr]){ s.push(neighbors); } } cout << endl; return 0; }