Compilare: user.cpp: In function ‘void DFP(int)’: user.cpp:18:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < G[Node].size(); ++ i) ^ user.cpp: In function ‘void DFM(int)’: user.cpp:32:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < GT[Node].size(); ++ i) ^ user.cpp: In function ‘int main()’: user.cpp:64:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < Ans.size(); ++ i) ^ user.cpp:66:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j < Ans[i].size(); ++ j) printf("%i ", Ans[i][j]); ^ user.cpp:42:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("ctc.in", "r", stdin); ^ user.cpp:43:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("ctc.out", "w", stdout); ^ user.cpp:45:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%i %i", &N, &M); ^ user.cpp:48:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%i %i", &A, &B); ^