uva 10330 最大流

拆点  将节点 i 的容量拆成从 i 到 i+n 的边的容量 套用最大流模板 ac

#include <cstdio>
#include <cstdlib>
#include <cmath>
#include <map>
#include <set>
#include <queue>
#include <stack>
#include <vector>
#include <sstream>
#include <string>
#include <cstring>
#include <algorithm>
#include <iostream>
#define maxn 210
#define INF 0x7fffffff
#define inf 10000000
#define MOD 1000000007
#define ull unsigned long long
#define ll long long
using namespace std;

int n, cap[maxn][maxn], a[maxn], m, flow[maxn][maxn], p[maxn];

int maxflow()
{
    queue<int> q;
    int f = 0;
    memset(flow, 0, sizeof(flow));
    while(true)
    {
        memset(a, 0, sizeof(a));
        a[0] = inf;
        q.push(0);
        while(!q.empty())
        {
            int u = q.front();
            q.pop();
            for(int i = 1; i <= n; ++ i)
            {
                if(!a[i] && cap[u][i] > flow[u][i])
                {
                    p[i] = u;
                    q.push(i);
                    a[i] = min(a[u], cap[u][i]-flow[u][i]);
                }
            }
        }
        if(!a[n]) break;
        for(int i = n; i != 0; i = p[i])
        {
            flow[p[i]][i] += a[n];
            flow[i][p[i]] -= a[n];
        }
        f += a[n];
    }
    return f;
}

int main()
{
    while(scanf("%d", &n) == 1)
    {
        memset(cap, 0, sizeof(cap));
        for(int i = 1; i <= n; ++ i)
        {
            int temp;
            scanf("%d", &temp);
            cap[i][i+n] = temp;
        }
        scanf("%d", &m);
        for(int i = 0; i < m; ++ i)
        {
            int x, y, c;
            scanf("%d%d%d", &x, &y, &c);
            cap[x+n][y] = c;
        }
        int a, b;
        scanf("%d%d", &a, &b);
        for(int i = 0; i < a; ++ i)
        {
            int x;
            scanf("%d", &x);
            cap[0][x] = inf;
        }
        for(int i = 0; i < b; ++ i)
        {
            int x;
            scanf("%d", &x);
            cap[x+n][2*n+1] = inf;
        }
        n = n*2+1;
        printf("%d\n", maxflow());
    }
    return 0;
}