Compilare: user.cpp: In function ‘int main()’: user.cpp:8:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("flori.in", "r", stdin); ^ user.cpp:9:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("flori.out", "w", stdout); ^ user.cpp:10:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &n, &k); ^ user.cpp:15:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &x); ^ cc1plus: warning: iteration 68u invokes undefined behavior [-Waggressive-loop-optimizations] user.cpp:39:17: note: containing loop for(int j = 1; j <= 70 ; ++j) ^