Compilare: user.cpp: In function ‘int main()’: user.cpp:126:39: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (ans.size() != query(1, inf - 1)) ^ user.cpp:67:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("centru2.in","r",stdin); ^ user.cpp:68:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("centru2.out","w",stdout); ^ user.cpp:70:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ user.cpp:71:74: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for (i = 1; i <= n; i++) scanf("%d%d", &I[i].l, &I[i].r), I[i].id = i; ^