#include <bits/stdc++.h>
using namespace std;
#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define llong long long

bool isKadomatsu(int x, int y, int z) {
    if(x == y || y == z || z == x) return false;
    return (x > y && z > y)
        || (x < y && z < y)
    ;
}

int main() {
    int n, m;
    cin >> n >> m;
    vector<int> vals(n);
    rep(i, n) cin >> vals[i];
    vector<vector<int>> graph(n);
    rep(i, m) {
        int a, b;
        cin >> a >> b;
        graph[a-1].push_back(b-1);
        graph[b-1].push_back(a-1);
    }

    rep(xi, n) {
        int x = vals[xi];
        for(int yi: graph[xi]) {
            if(xi == yi) continue;
            int y = vals[yi];
            for(int zi: graph[yi]) {
                if(zi == yi || zi == xi) continue;
                int z = vals[zi];
                if(isKadomatsu(x, y, z)) {
                    cout << "YES\n";
                    return 0;
                }
            }
        }
    }
    cout << "NO\n";
}