Compilare: user.cpp: In function ‘int nrdiv()’: user.cpp:17:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0;i<exp.size();++i) ^ user.cpp: In function ‘int main()’: user.cpp:62:29: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("maxd.in","r",stdin); ^ user.cpp:63:31: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("maxd.out","w",stdout); ^ user.cpp:65:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&X,&Y); ^