#include <cstdio>
#include <cstring>
#include <algorithm>
using namespace std;

const int maxn = 200 + 5, maxm = 20000 + 5, inf = 0x3f3f3f3f;
struct Edge {
    int to, cap, flow, next;
} edge[maxm << 2];

int tot, head[maxn << 1], que[maxn << 1], dep[maxn << 1], cur[maxn << 1], sta[maxn << 1];

void init() {
    tot = 2;
    memset(head, -1, sizeof head);
}

void addedge(int u, int v, int w, int rw = 0) {
    edge[tot].to = v; edge[tot].cap = w; edge[tot].flow = 0;
    edge[tot].next = head[u]; head[u] = tot ++;
    edge[tot].to = u; edge[tot].cap = rw; edge[tot].flow = 0;
    edge[tot].next = head[v]; head[v] = tot ++;
}

bool bfs(int s, int t, int n) {
    int front = 0, tail = 0;
    memset(dep, -1, sizeof dep[0] * (n + 1));
    dep[s] = 0;
    que[tail ++] = s;
    while(front < tail) {
        int u = que[front ++];
        for(int i = head[u]; ~i; i = edge[i].next) {
            int v = edge[i].to;
            if(edge[i].cap > edge[i].flow && dep[v] == -1) {
                dep[v] = dep[u] + 1;
                if(v == t) return true;
                que[tail ++] = v;
            }
        }
    }
    return false;
}

int dinic(int s,int t, int n) {
    int maxflow = 0;
    while(bfs(s, t, n)) {
        for(int i = 0; i <= n; i ++) cur[i] = head[i];
        int u = s, tail = 0;
        while(cur[s] != -1) {
            if(u == t) {
                int tp = inf;
                for(int i = tail - 1; i >= 0; i --)
                    tp = min(tp, edge[sta[i]].cap - edge[sta[i]].flow);
                maxflow += tp;
                for(int i = tail - 1; i >= 0; i --) {
                    edge[sta[i]].flow += tp;
                    edge[sta[i] ^ 1].flow -= tp;
                    if(edge[sta[i]].cap - edge[sta[i]].flow == 0) tail = i;
                }
                u = edge[sta[tail] ^ 1].to;
            }
            else if(cur[u] != -1 && edge[cur[u]].cap > edge[cur[u]].flow && dep[u] + 1 == dep[edge[cur[u]].to]) {
                sta[tail ++] = cur[u];
                u = edge[cur[u]].to;
            }
            else {
                while(u != s && cur[u] == -1)
                    u = edge[sta[-- tail] ^ 1].to;
                cur[u] = edge[cur[u]].next;
            } 
        }
    }
    return maxflow;
}

int main() {
    int n, m, s, t, u, v, cost;
    while(~scanf("%d %d", &n, &m)) {
        init();
        scanf("%d %d", &s, &t);
        for(int i = 1; i <= n; i ++) {
            scanf("%d", &cost);
            addedge(i, n + i, cost);
        }
        for(int i = 1; i <= m; i ++) {
            scanf("%d %d", &u, &v);
            addedge(u + n, v, inf);
            addedge(v + n, u, inf);
        }
        printf("%d\n", dinic(s, t + n, 2 * n));
    }
    return 0;
}