Compilare: main.cpp: In function 'void dfs(long long int)': main.cpp:22:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j = 0 ; j < G[u].size() && ok == 1 ; j ++) ~~^~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:79:43: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("funnygraph.in" , "r" , stdin); ^ main.cpp:80:45: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("funnygraph.out" , "w" , stdout); ^ main.cpp:82:32: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%lld%lld" , &n , &m); ^ main.cpp:85:48: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%lld%lld%lld" , &tx , &ty , &tz); ^