#include <bits/stdc++.h>

using namespace std;

#define REP(i,n) for(int i=0; i<(int)(n); i++)

int n, m;
int a[1000];
vector<int> edges[1000];

int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);

  cin >> n >> m;
  REP (i, n) cin >> a[i];
  REP (i, m) {
    int u, v;
    cin >> u >> v;
    --u, --v;
    edges[u].push_back(v);
    edges[v].push_back(u);
  }

  bool ret = false;
  REP (i, n) {
    int x2 = a[i];
    REP (j, edges[i].size()) REP (k, edges[i].size()) {
      int x1 = a[edges[i][j]];
      int x3 = a[edges[i][k]];
      if (x1 == x2 || x2 == x3 || x3 == x1)
        continue;
      if (x2 == max({x1, x2, x3}) || x2 == min({x1, x2, x3}))
        ret = true;
    }
  }

  cout << (ret ? "YES" : "NO") << endl;
  
  return 0;
}