Compilare: user.cpp: In function ‘void Solve()’: user.cpp:53:43: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < Hash[x % MOD].size(); ++i) ^ user.cpp:52:22: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%lld", &x); ^ user.cpp: In function ‘int main()’: user.cpp:86:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for(scanf("%d", &n); n; --n) ^