Compilare: main.cpp: In function 'void dfs(int)': main.cpp:15:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j = 0 ; j < G[u].size() ; j ++) ~~^~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:59:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j = 0 ; j < T[ord[i]].size() ; j ++) ~~^~~~~~~~~~~~~~~~~~ main.cpp:69:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j = 0 ; j < G[ord[i]].size() ; j ++) ~~^~~~~~~~~~~~~~~~~~ main.cpp:26:36: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("pm2.in" , "r" , stdin); ^ main.cpp:27:38: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("pm2.out" , "w" , stdout); ^ main.cpp:29:21: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d" , &n); ^ main.cpp:31:28: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d" , &v[i]); ^ main.cpp:34:25: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d" , &m); ^ main.cpp:37:29: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d" , &x); ^