Compilare: user.cpp: In function ‘void heap_down(int, int)’: user.cpp:13:12: warning: suggest explicit braces to avoid ambiguous ‘else’ [-Wparentheses] if (2*poz+1<=n) if ((a[2*poz]<a[poz])||(a[2*poz+1]<a[poz])){ ^ user.cpp: In function ‘int main()’: user.cpp:23:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("algsort.in","r",stdin); ^ user.cpp:24:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("algsort.out","w",stdout); ^ user.cpp:25:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ user.cpp:27:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &a[i]); ^