#include "bits/stdc++.h"
using namespace std;
#define FOR(i,j,k) for(int (i)=(j);(i)<(int)(k);++(i))
#define rep(i,j) FOR(i,0,j)
#define each(x,y) for(auto &(x):(y))
#define mp make_pair
#define mt make_tuple
#define all(x) (x).begin(),(x).end()
#define debug(x) cout<<#x<<": "<<(x)<<endl
#define smax(x,y) (x)=max((x),(y))
#define smin(x,y) (x)=min((x),(y))
#define MEM(x,y) memset((x),(y),sizeof (x))
#define sz(x) (int)(x).size()
#define pb push_back
typedef long long ll;
typedef pair<int, int> pii;
typedef vector<int> vi;
typedef vector<ll> vll;

int check(int x, int y, int z) {
    if (x != y&&y != z&&z != x && ((y > x&&y > z) || (y < x&&y < z)))return 1;
    return 0;
}

int N, M;
vi G[1003];
int A[1003];

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

    cin >> N >> M;
    rep(i, N)cin >> A[i];
    rep(i, M) {
        int u, v;
        cin >> u >> v;
        --u; --v;
        G[u].push_back(v);
        G[v].push_back(u);
    }

    rep(u, N) {
        each(v, G[u]) {
            each(w, G[v])if (w != u) {
                int ok = check(A[u], A[v], A[w]);
                if (ok) {
                    cout << "YES" << endl;
                    return 0;
                }
            }
        }
    }

    cout << "NO" << endl;
}