Compilare: user.cpp: In function ‘long long int digit_found(int)’: user.cpp:53:6: warning: unused variable ‘index’ [-Wunused-variable] int index = 0; ^ user.cpp: In function ‘void read_input()’: user.cpp:28:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &digit[i]); ^ user.cpp:32:17: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &k); ^ user.cpp: In function ‘int main()’: user.cpp:103:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("test.in", "r", stdin); ^ user.cpp:104:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("test.out", "w", stdout); ^ user.cpp:106:17: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^