Compilare: user.cpp: In function ‘void back(unsigned int, unsigned int)’: user.cpp:9:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(a[i] > lim / pr) return ; ^ user.cpp:18:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(p == k){ ^ user.cpp: In function ‘int main()’: user.cpp:42:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("numar2.in", "r", stdin); ^ user.cpp:43:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("numar2.out", "w", stdout); ^ user.cpp:44:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &n, &p); ^ user.cpp:46:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &a[i]); ^