Compilare: user.cpp: In function ‘int main()’: user.cpp:23:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<v[tmp1].size();++i) ^ user.cpp:43:41: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<v[q[st]].size();++i){ ^ user.cpp:14:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("sortaret.in","r",stdin); ^ user.cpp:15:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("sortaret.out","w",stdout); ^ user.cpp:18:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&n,&m); ^ user.cpp:22:35: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&tmp1,&tmp2); ^