#include<bits/stdc++.h>
using namespace std;
#define int long long
const int inf = 2000000005;
/*
 *                                                     __----~~~~~~~~~~~------___
 *                                    .  .   ~~//====......          __--~ ~~
 *                    -.            \_|//     |||\\  ~~~~~~::::... /~
 *                 ___-==_       _-~o~  \/    |||  \\            _/~~-
 *         __---~~~.==~||\=_    -_--~/_-~|-   |\\   \\        _/~
 *     _-~~     .=~    |  \\-_    '-~7  /-   /  ||    \      /
 *   .~       .~       |   \\ -_    /  /-   /   ||      \   /
 *  /  ____  /         |     \\ ~-_/  /|- _/   .||       \ /
 *  |~~    ~~|--~~~~--_ \     ~==-/   | \~--===~~        .\
 *           '         ~-|      /|    |-~\~~       __--~~
 *                       |-~~-_/ |    |   ~\_   _-~            /\
 *                            /  \     \__   \/~                \__
 *                        _--~ _/ | .-~~____--~-/                  ~~==.
 *                       ((->/~   '.|||' -_|    ~~-/ ,              . _||
 *                                  -_     ~\      ~~---l__i__i__i--~~_/
 *                                  _-~-__   ~)  \--______________--~~
 *                                //.-~~~-~_--~- |-------~~~~~~~~
 *                                       //.-~~~--\
 *                       ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*/
vector<int>p[200005];
struct edge{
	int fl,to;
}e[200005];
int n,m,s,t,head = 1;
int cur[2005],dis[2005];
void add(int a,int b,int c){
	e[++head].to = b,e[head].fl = c;
	p[a].push_back(head);
	e[++head].to = a,e[head].fl = 0;
	p[b].push_back(head);return;
}
bool bfs(){
	memset(cur,0,sizeof(cur));
	memset(dis,63,sizeof(dis));
	queue<int>q;
	q.push(s);dis[s] = 0;
	//cout << s << endl;
	while(!q.empty()){
		int now = q.front();q.pop();
		//cout << now << endl;
		for(int i =0;i<p[now].size();i++){
			int to = e[p[now][i]].to,fl = e[p[now][i]].fl;
		//	cout << " " << to << endl;
			if(!fl)continue;
			if(dis[now]+1<dis[to]){
				dis[to] = dis[now]+1;
				q.push(to);
			}
		}
	}return (dis[t]<=2*n);
}int dfs(int now,int f){
	if(now == t or !f)return f;
	int res = 0;
	for(int i = cur[now];i<p[now].size();i++){
		cur[now] = i;
		int to = e[p[now][i]].to,fl = e[p[now][i]].fl,nw = 0;
		if(!fl or dis[now]+1!=dis[to])continue;
		if(nw = dfs(to,min(f,fl))){
			res+=nw,f-=nw;
			e[p[now][i]].fl-=nw,e[p[now][i]^1].fl+=nw;
			if(!f)break;
		}
	}return res;
}int Dinic(){
	int ans = 0;
	while(bfs()){
	//	cout << 1 << endl;
		ans+=dfs(s,inf);
	}return ans;
}int x[200005]; 
signed main(){
	cin>>n>>m;s = 2*n+1,t = 2*n+2;
	for(int i = 1;i<=n;i++)cin >> x[i];
	for(int i = 1;i<=m;i++){
		int a,b;cin >> a >> b;
		add(a,b,inf);add(a+n,b+n,inf);
	}for(int i = 1;i<=n;i++){
		if(x[i]>=0)add(s,i,x[i]),add(i+n,t,x[i]);
		else add(i,i+n,-x[i]);
	}int sum = 0;for(int i = 1;i<=n;i++)sum+=x[i]*(x[i]>=0);
	int res = Dinic();
	cout << sum-res << endl;
	return 0;
}