poj-1459 Power Network *

/*
 * 最大流    Edmonds-Karp
 *
 * 加入两个节点 S 和 T
 * S 与 所有 power stations相连 ； 所有 consumers 与 T 相连
 *
 */

#include <iostream>
#include <cstring>
using namespace std;

const int inf = 100000000;
const int maxN = 100 + 5;
int n, np, nc, m, l[maxN][maxN], s, t;
int q[maxN], maxFlow, pre[maxN];

void addFlow(){
    int minL = inf, cur = t;
    while(cur != s){
        if(l[pre[cur]][cur] < minL)
            minL = l[pre[cur]][cur];
        cur = pre[cur];
    }

    cur = t;
    while(cur != s){
        l[pre[cur]][cur] -= minL;
        l[cur][pre[cur]] += minL;
        cur = pre[cur];
    }

    maxFlow += minL;
}


void fulk(){
    while(true){
        memset(pre, -1, sizeof(pre));
        int head = 0, tail = 0, cur;
        q[tail++] = s;

        while(head != tail){
            cur = q[head++];
            for(int j=0; j<=n+1; j++){
                if(l[cur][j] != 0 && pre[j] == -1){
                    pre[j] = cur;
                    q[tail++] = j;
                }
            }
            if(pre[t] != -1) break;
        }
        if(pre[t] != -1) addFlow();
        else break;
    }
}

int main(){
    while(cin >> n){
        cin >> np >> nc >> m;

        memset(l, 0, sizeof(l));
        s = 0, t = n + 1, maxFlow = 0;
        char tmp;
        int u, v, z;
        for(int i=1; i<=m; i++){
            cin >> tmp >> u >> tmp >> v >> tmp >> z;
            l[u+1][v+1] = z;
        }
        for(int i=1; i<=np; i++){
            cin >> tmp >> u >> tmp >> z;
            l[s][u+1] = z;
        }
        for(int i=1; i<=nc; i++){
            cin >> tmp >> u >> tmp >> z;
            l[u+1][t] = z;
        }


        fulk();

        cout << maxFlow << endl;




    }


    return 0;
}