#include <bits/stdc++.h> using namespace std; long long collisions(std::vector<long long> x); int hack(){ for (int i = 2; i<=500000; i++){ if (collisions({1, i})) return i-1; } }

hack.cpp: In function 'int hack()':
hack.cpp:10:1: warning: control reaches end of non-void function [-Wreturn-type]
   10 | }
      | ^