Compilare: user.cpp: In function ‘int main()’: user.cpp:15:58: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for (int i = 0; i <= 26; ++i) scanf("%lld", &cost[i]); ^ user.cpp:17:26: warning: ignoring return value of ‘char* fgets(char*, int, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fgets(s, 1000001, in); ^ user.cpp:18:22: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%lld", &l); ^