Compilare: main.cpp: In function 'void DFS(int)': main.cpp:17:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < g[x].size(); ++i) ~~^~~~~~~~~~~~~ main.cpp: In function 'void DFST(int, int)': main.cpp:28:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < gt[x].size(); ++i) ~~^~~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:60:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0; j < ctc[i].size(); ++j) ~~^~~~~~~~~~~~~~~ main.cpp:35:34: 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); ^ main.cpp:36:36: 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); ^ main.cpp:38:28: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf ("%d %d", &n, &m); ^ main.cpp:40:31: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &x, &y); ^