#include<bits/stdc++.h>
using namespace std;

#define int long long

const int maxn=1e4+100;
const int mod=998244353;

int n,m,c[maxn],a[maxn],in[maxn],vis[maxn],f[maxn];
vector<int>g[maxn],topo;
queue<int>Q;


void dfs(int x){
	vis[x]=1;
	for(auto y:g[x])dfs(y);
}

inline void update(){
	for(auto x:topo){
		int k=f[x]/c[x];
		for(auto y:g[x])if(vis[y]){
			f[y]+=k;
		}
		f[x]%=c[x];
	}
}

signed main(void){
	ios::sync_with_stdio(0);
	cin.tie(0);cout.tie(0);
	cin>>n>>m;
	for(int i=1;i<=n;++i)cin>>c[i];
	while(m--){
		int u,v;cin>>u>>v;
		g[u].push_back(v);
	}
	dfs(1);
	for(int i=1;i<=n;++i)if(vis[i]){
		for(auto y:g[i])if(vis[y])++in[y];
	}
	Q.push(1);
	while(Q.size()){
		int x=Q.front();Q.pop();
		topo.push_back(x);
		for(auto y:g[x])if(vis[y]){
			--in[y];
			if(in[y]==0)Q.push(y);
		}
	}
	f[1]=c[1];
	int ans=c[1];
	update();
	for(int ii=1;ii<topo.size();++ii){
		int x=topo[ii];
		if(f[x]==0)continue;
		int p=c[x]/__gcd(f[x],c[x]);
		ans=ans*p%mod;
		for(int i=1;i<=n;++i)f[i]*=p;
		update();
	}
	cout<<ans;
	return 0;
}