#include<bits/stdc++.h>
#define int long long
#define rep(i,a,b) for(int i=(a);i<=(b);i++)
#define per(i,a,b) for(int i=(b);i>=(a);i--)
#define endl "\n"
#define For(i,u) for(int i=head[u];i;i=e[i].next)
#define V vector<int>
#define VV vector<V>
#define Debug(a) cout<<"QwQ "<<a<<endl;
const int MOD=1e9+7;

using namespace std;

int n,m,s,t;

int read()
{
	int x=0,f=1;char ch=getchar();
	while(ch<'0'||ch>'9'){if(ch=='-') f=-1;ch=getchar();}
	while(ch>='0'&&ch<='9'){x=x*10+ch-'0';ch=getchar();}
	return x*f;
}

string reads()
{
	char ch=getchar();string s;
	while(ch<'a'||ch>'z'){ch=getchar();}
	while(ch>='a'&&ch<='z'){s+=ch;ch=getchar();}
	return s;
}

char readc()
{
	char ch=getchar();
	while(ch<'a'||ch>'z') ch=getchar();
	return ch;
}

// down is mytrue code ------------------------------

const int M=5050,N=1010,INF=(1ll<<31);

struct
{
	int to,dis,next;
}e[M*4];

int cnt=1,head[N],ans,dis[N],cur[N];

void add(int u,int v,int w)
{
	e[++cnt].to=v;
	e[cnt].next=head[u];
	e[cnt].dis=w;
	head[u]=cnt;
	swap(u,v);
	w=0;
	e[++cnt].to=v;
	e[cnt].next=head[u];
	e[cnt].dis=w;
	head[u]=cnt;
}

bool bfs()
{
	memset(dis,-1 ,sizeof(dis));
	dis[s]=0;
	queue<int>q;
	q.push(s);
	while(!q.empty())
	{
		int u=q.front();
		q.pop();
		for(int i=head[u];i!=0;i=e[i].next)
		{
			int v=e[i].to;
		//if(dis[v]&&e[i].dis==0)
			if((dis[v]==-1)&&(e[i].dis!=0))
			{
				dis[v]=dis[u]+1;
				q.push(v);
			}
		}
	}
	if(dis[t]==-1)
	{
		return false;
	}
	else return true;
}
int dfs(int u,int flo)
{
	if(u==t) {
		ans+=flo;
		return flo;
	}
	int used=0;
	for(int i=cur[u];i!=0;i=e[i].next)
	{
		cur[u]=e[i].next;
		int v=e[i].to;
		if(dis[v]==dis[u]+1&&e[i].dis>0)
		{
			int d=dfs(v,min(flo-used,e[i].dis));
			if(d){
				e[i].dis-=d;e[i^1].dis+=d;used+=d;
			}
			if(used==flo)return flo;
		}
	}
	return used;
}
void run()
{
	while(bfs())
	{
		for(int i=1;i<=n*2+2;i++)cur[i]=head[i]; 
		dfs(s,INF);
	}
}

int a[N];

signed main()
{
//	freopen("dt.in","r",stdin);
	n=read(),m=read();
	s=n*2+2,t=n*2+1;
	int sum=0;
	rep(i,1,n)
	{
		a[i]=read();
		if(a[i]>=0) add(s,i,a[i]),add(i,i+n,0),add(i+n,t,a[i]),sum+=a[i];
		else add(s,i,0),add(i,i+n,-a[i]),add(i+n,t,0);
	} 
	rep(i,1,m)
	{
		int u=read(),v=read();
		add(u,v,INF);
		add(u+n,v+n,INF);
	}
	run();
	cout<<sum-ans<<endl;
	return 0;
}