Compilare: user.cpp: In function ‘int main()’: user.cpp:22:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<st.size();i++) ^ user.cpp:29:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=f[m];i<st.size();i++) ^ user.cpp:34:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<st.size()-1;i++) ^ user.cpp:8:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("impartire.in","r",stdin); ^ user.cpp:9:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("impartire.out","w",stdout); ^ user.cpp:11:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&m,&n); ^