Compilare: user.cpp: In function ‘int main()’: user.cpp:34:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0; i<g[t].size(); ++i) ^ user.cpp:63:39: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0; i<g[x2].size(); ++i) ^ user.cpp:14:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("fmcm.in","r",stdin); ^ user.cpp:15:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("fmcm.out","w",stdout); ^ user.cpp:17:34: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d%d",&n,&m,&s,&d); ^ user.cpp:20:38: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d%d",&x,&y,&c,&z); ^