POJ1698 Alice's Chance 最大流

不会sap，邻接矩阵过。

#include <cstdlib>
#include <cstring>
#include <cstdio> 
#include <queue>
#define MAXN 375
#define INF 0x3f3f3f3f
using namespace std;

int cap[MAXN+1][MAXN+1], flow[MAXN+1][MAXN+1], N;
int p[MAXN+1], c[MAXN+1];
int seq[25][15], maxflow;

inline void init()
{
    maxflow = 0;
    memset(cap, 0, sizeof (cap));
    memset(flow, 0, sizeof (flow));
}

inline int min(int a, int b) 
{
    return a < b ? a : b;
}

void bfs()
{
    int finish = 0, pos;
    while (!finish) { 
        memset(c, 0, sizeof (c));  // 记录推送流量
        c[0] = INF;
        queue<int>q;
        q.push(0);
        while (!q.empty()) {
            if (c[MAXN])
                break;
            pos = q.front();
            q.pop();
            for (int i = 0; i <= MAXN; ++i) {
                if (!c[i] && flow[pos][i] < cap[pos][i]) {
                    c[i] = min(c[pos], cap[pos][i]-flow[pos][i]);
                    p[i] = pos;
                    q.push(i);
                }
            }
        } 
        maxflow -= c[MAXN];
        if (c[MAXN] == 0) {
            finish = 1;
            break;
        }
        pos = MAXN;
        while (pos != 0) { 
            flow[p[pos]][pos] += c[MAXN];
            flow[pos][p[pos]] -= c[MAXN];
            pos = p[pos];
        }
    }
}

int main()
{
    int T;
    scanf("%d", &T);
    while (T--) {
        init();
        scanf("%d", &N);
        for (int i = 0; i < N; ++i) {
            for (int j = 0; j < 9; ++j) {
                scanf("%d", &seq[i][j]);
            }
            maxflow += seq[i][7];
            cap[0][i+1] = seq[i][7];
            for (int j = 0; j < 7; ++j) {
                if (seq[i][j]) {
                    for (int k = 0; k < seq[i][8]; ++k) {
                        cap[i+1][k*7+N+1+j] = 1;
                        cap[k*7+N+1+j][MAXN] = 1;
                    }
                }
            }
        }  
        bfs();
        if (maxflow == 0) {
            puts("Yes");
        }
        else {
            puts("No");
        }
    }
    return 0;
}