#include<cstdio>
#include<cstring>
#include<vector>
#include<queue>
#include<stack>
#include<algorithm>
#include<cmath>
#include<climits>
#include<string>
#include<set>
#include<numeric>
#include<map>
#include<iostream>
using namespace std;
#define rep(i,n) for(int i = 0;i<((int)(n));i++)
#define reg(i,a,b) for(int i = ((int)(a));i<=((int)(b));i++)
#define irep(i,n) for(int i = ((int)(n)-1);i>=0;i--)
#define ireg(i,a,b) for(int i = ((int)(b));i>=((int)(a));i--)
typedef long long ll;
typedef pair<ll, ll> mp;
ll mod = 1e9+7;
ll inf = 1e18;

//WA

int main(void){
	bool ans=false;
	ll n,m,a[1010],b,c;
	vector<ll> v[1010];
	cin>>n>>m;
	reg(i,1,n)cin>>a[i];
	rep(i,m){
		cin>>b>>c;
		v[b].push_back(c);
		v[c].push_back(b);
	}
	reg(p,1,n){
		rep(i,v[p].size()){
			ll q = v[p][i];
			rep(j,v[q].size()){
				ll r = v[q][j];
				if(a[p]==a[r])continue;
				if(a[q]>a[p] && a[q]>a[r]){
					ans=true;
					break;
				};
				if(a[q]<a[p] && a[q]<a[r]){
					ans=true;
					break;
				};
			}
			if(ans)break;
		}
		if(ans)break;
	}
	if(ans){
		printf("YES\n");
	}else{
		printf("NO\n");
	}
}