#include <iostream>
#include <cstdio>
#include <vector>
#include <algorithm>
#include <utility>
#include <set>

using namespace std;

int main() {
	int n, m, u, v;
	cin >> n >> m;

	vector<int> a(n, 0);
	for (int i = 0; i < n; i++) {
		cin >> a[i];
	}

	vector<vector<set<int>>> connect(n, vector<set<int>>(2));
	for (int i = 0; i < m; i++) {
		cin >> u >> v;
		u--;
		v--;

		int au = a[u];
		int av = a[v];

		if (au == av) {
			continue;
		}

		connect[u][av > au].insert(av);
		connect[v][au > av].insert(au);
	}

	bool ok = false;
	for (auto x : connect) {
		if (x[0].size() >= 2 || x[1].size() >= 2) {
			ok = true;
		}
	}

	cout << (ok ? "YES" : "NO") << endl;
	return 0;
}