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

vector<int>E[1000];
int a[1000];
int main(){
	int n,m;scanf("%d%d",&n,&m);
	rep(i,n)scanf("%d",&a[i]);
	rep(i,m){
		int s,t;scanf("%d%d",&s,&t);s--;t--;
		E[s].push_back(t);E[t].push_back(s);
	}
	rep(i,n){
		for(auto u:E[i]){
			for(auto v:E[i]){
				if(u==v)continue;
				if(a[i]==a[u]||a[i]==a[v]||a[u]==a[v])continue;
				if((a[i]<a[u]&&a[i]<a[v])||(a[i]>a[u]&&a[i]>a[v])){
					puts("YES");return 0;
				}
			}
		}
	}
	puts("NO");
}