Compilare: user.cpp: In function ‘int DFS(int)’: user.cpp:20:42: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < graph[node].size(); i++) { ^ user.cpp:26:1: warning: no return statement in function returning non-void [-Wreturn-type] } ^ user.cpp: In function ‘int df(int)’: user.cpp:31:43: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < revers[node].size(); i++) { ^ user.cpp:36:1: warning: no return statement in function returning non-void [-Wreturn-type] } ^ user.cpp: In function ‘int solve()’: user.cpp:66:45: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0; j < sol[i].size(); j++) { ^ user.cpp:72:1: warning: no return statement in function returning non-void [-Wreturn-type] } ^