Compilare: user.cpp: In function ‘int src(int)’: user.cpp:24:14: warning: statement has no effect [-Wunused-value] for (step; step; step >>= 1) ^ user.cpp:25:49: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (to + step <= n && p[to+step].val <= val) ^ user.cpp: In function ‘int main()’: user.cpp:55:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("psir.in", "r", stdin); ^ user.cpp:56:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("psir.out", "w", stdout); ^ user.cpp:58:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ user.cpp:60:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%u", &a[i]); ^