#include<iostream>
#include<cstdio>
#include<cstring>
#include <cstdlib>  
#include <cmath>   
#include<cctype>
#include<string>
#include<set>
#include<iomanip>
#include <map>
#include<algorithm>
#include <functional>
#include<vector>
#include<climits>
#include<stack>
#include<queue>
#include <deque>
#include <climits>
#include <typeinfo>
#include <utility> 
#define all(x) (x).begin(),(x).end()
#define rep(i,m,n) for(int i = m;i < n;++i)
#define pb push_back
#define fore(i,a) for(auto &i:a)
#define rrep(i,m,n) for(int i = m;i >= n;--i)
#define INF INT_MAX/2
using namespace std;
using ll = long long;
using R = double;
using Data = pair<ll, vector<int>>;
const ll MOD = 1e9 + 7;
const ll inf = 1LL << 50;
struct edge { ll from; ll to; ll cost; };

int n, m;
int a[1010];
vector<int>e[1010];
int used[1010];

int check(vector<int>v) {
	vector<pair<int, int>>temp;
	rep(i, 0, 3)temp.pb({v[i],i});
	sort(all(temp));
	if (v[0] != v[1] && v[1] != v[2] && v[2] != v[0]) {
		if (temp[0].second == 1 || temp[2].second == 1)return true;
		else return false;
	}
	else {
		return false;
	}

}

int dfs(int n,vector<int>v) {
	if (v.size() == 3)return check(v);

	int ret = 0;
	fore(x,e[n]) {
		if (!used[x]) {
			vector<int>temp = v;
			temp.pb(a[x]);
			used[x] = 1;
			int t = dfs(x,temp);
			if (t)ret = 1;
			used[x] = 0;
		}
	}
	return ret;
}


int main() {
	cin >> n >> m;
	rep(i, 0, n) {
		cin >> a[i];
	}
	rep(i, 0, m) {
		int u, v;
		cin >> u >> v;
		u--, v--;
		e[u].pb(v);
		e[v].pb(u);
	}

	rep(i,0,n) {
		vector<int>temp;
		temp.pb(a[i]);
		used[i] = 1;
		if (dfs(i, temp)) {
			cout << "YES" << endl;
			return 0;
		}
		used[i] = 0;
	}
	cout << "NO" << endl;

	return 0;
}