#include <iostream>
#include <vector>
#include <string>
#include <cstring>
#include <math.h>
#include <cmath>
#include <limits.h>
#include <map>
#include <set>
#include <queue>
#include <algorithm>
#include <functional>
#include <stdio.h>
using namespace std;

long long MOD = 1000000007;

bool isKadomatsu( int a, int b, int c ) {
    return ( a < b && b > c && a != c ) || ( a > b && b < c && a != c );
}

int main() {
    int N,M;
    cin >> N >> M;
    vector<long long> A(N);
    for ( int i = 0; i < N; i++ ) {
        cin >> A[i];
    }
    vector< vector<int> > P( M,vector<int>(2) );
    for ( int i = 0; i < M; i++ ) {    
        cin >> P[i][0] >> P[i][1];
        P[i][0]--; P[i][1]--;
    }
    for ( int i = 0; i < M; i++ ) {
    for ( int j = i+1; j < M; j++ ) {
        for ( int a = 0; a < 2; a++ ) {
        for ( int b = 0; b < 2; b++ ) {
            if ( P[i][a] == P[j][b] && isKadomatsu( A[P[i][1-a]],A[P[i][a]],A[P[j][1-b]] ) ) {
                cout << "YES" << endl; return 0;
            }
        }
        }
    }
    }
    cout << "NO" << endl;
    
    return 0;
}