Compilare: user.cpp: In function ‘int main()’: user.cpp:107:11: warning: unused variable ‘fout’ [-Wunused-variable] FILE *fout=fopen("cmap.out","w"); ^ user.cpp:108:26: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin , "%d",&n); ^ user.cpp:113:38: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin,"%lld %lld",&x,&y); ^