Compilare: user.cpp: In function ‘void solve()’: user.cpp:21:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(q=0;q<G[j].size();q++){ ^ user.cpp:29:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<G[0].size();i++) ^ user.cpp: In function ‘int main()’: user.cpp:37:16: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen(iN); ^ user.cpp:38:17: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen(ouT); ^ user.cpp:39:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&n,&m); ^ user.cpp:41:33: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d",&x,&y,&c); ^