Compilare: user.cpp: In function ‘int binary(int, long long int)’: user.cpp:34:42: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (ans + step < list[node].size()) ^ user.cpp: In function ‘void dfs(int)’: user.cpp:48:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 1; i < list[node].size(); i++) ^ user.cpp:51:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 0; i < list[node].size(); i++) { ^ user.cpp: In function ‘int main()’: user.cpp:71:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("arb3.in","r",stdin); ^ user.cpp:72:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("arb3.out","w",stdout); ^ user.cpp:74:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &n, &q); ^ user.cpp:76:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &x); ^ user.cpp:80:50: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for (i = 1; i <= n; i++) scanf("%lld", &v[i]); ^ user.cpp:84:32: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%lld", &x, &y); ^