Compilare: user.cpp: In function ‘int main()’: user.cpp:12:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("klexico.in", "r", stdin); ^ user.cpp:13:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("klexico.out", "w", stdout); ^ user.cpp:15:38: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d\n%s\n", &n, &k, a+1); ^