Compilare: user.cpp: In function ‘int main()’: user.cpp:34:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<bands.size();i++) ^ user.cpp:27:28: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d %d",&N,&M); ^ user.cpp:30:51: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d %d",&P[i].first,&P[i].second); ^ user.cpp:47:32: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d %d",&x,&y); ^