/*
** 无向图拆点，求最大流，最大流即为割点个数。
*/
#include <iostream>
#include <cstdio>
#include <cstring>
#include <queue>
#include <algorithm>
using namespace std;
const int maxn = 410;
const int maxm = 100100;
const int INF = 200000000;
struct node{
int v,flow,next;
}edge[maxm];
int head[maxn],dis[maxn],aug[maxn];
int n,m,s,t,id;
void add_edge(int u,int v,int flow){
edge[id].v = v;edge[id].flow = flow;edge[id].next = head[u];head[u] = id++;
edge[id].v = u;edge[id].flow = 0 ;edge[id].next = head[v];head[v] = id++;
}
void init(){
int cost,u,v;
memset(head,-1,sizeof(head));id = 0;
for(int i = 1; i <= n; i++){
scanf("%d",&cost);
add_edge(i,i+n,cost);
}
//v入，v+n出
while( m-- ){
scanf("%d%d",&u,&v);
add_edge(u+n,v,INF);
add_edge(v+n,u,INF);
}
add_edge(0,s,INF);
add_edge(t+n,n*2+1,INF);
s = 0,t = n*2+1;
}
bool bfs(){
memset(dis,-1,sizeof(dis));
queue<int>que;
dis[s] = 0;
que.push(s);
while(!que.empty()){
int u = que.front();
que.pop();
for(int id = head[u]; id != -1; id = edge[id].next){
int v = edge[id].v;
if( edge[id].flow > 0 && dis[v] == -1){
dis[v] = dis[u] + 1;
que.push(v);
}
}
}
return dis[t] != -1;
}
int min(int x,int y){
return x < y ? x : y;
}
int dinic(int u,int flow){
if(u == t || flow == 0)return flow;
int tmp = flow;
for(int id = head[u]; id != -1; id = edge[id].next){
int v = edge[id].v;
if( edge[id].flow > 0 && dis[v] == dis[u] + 1){
int tt = dinic(v,min(tmp,edge[id].flow));
tmp -= tt;
edge[id].flow -= tt;
edge[id^1].flow += tt;
if(tmp == 0) break;
}
}
return flow - tmp;
}
int main(){
//freopen("in.txt","r",stdin);
while(~scanf("%d%d",&n,&m)){
scanf("%d%d",&s,&t);
init();
// cout << id << endl;
int max_flow = 0;
while(bfs())
max_flow += dinic(s,INF);
printf("%d
",max_flow);
}
return 0;
}