Compilare: user.cpp: In function ‘void solve(int, int)’: user.cpp:50:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if((m[0][pm]*(sf-inc+1))>costm) ^ user.cpp: In function ‘int main()’: user.cpp:81:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(cost>costm) ^ user.cpp:62:30: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(buff,1,20000,stdin); ^ user.cpp: In function ‘void read(long int&)’: user.cpp:17:103: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] while(buff[pos] < '0' || buff[pos] > '9') if(++pos == 20000) fread(buff, 1, 20000, stdin), pos = 0; ^ user.cpp:22:65: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] if(++pos == 20000) fread(buff, 1, 20000, stdin), pos = 0; ^