Compilare: user.cpp: In function ‘void build_nr_of_coins_used()’: user.cpp:50:20: warning: left operand of comma operator has no effect [-Wunused-value] for (int i=1; i<=nr_of_types, total_sum; i++) ^ user.cpp: In function ‘void read()’: user.cpp:38:60: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(in, "%d%d%lld", &nr_of_types, &base, &total_sum); ^ user.cpp:41:53: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(in, "%d%lld", &COIN[i].A, &COIN[i].B); ^