Submission #3417810

---

Source Code Expand

#include <algorithm>
#include <iostream>
#include <vector>
using namespace std;

int main(){
  int N, M;
  cin >> N >> M;
  vector<int> C(N,0);
  for(int i = 0; i < M; ++i){
    int a, b;
    cin >> a >> b;
    --a,--b;
    if(!a) ++C[b];
    if(b == N-1) ++C[a];
  }
  if(*max_element(C.begin(), C.end()) > 1) cout << "POSSIBLE" << endl;
  else cout << "IMPOSSIBLE" << endl;
  return 0;
}

Submission Info

Judge Result