最大流样例不过全 Wa 求助
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最大流样例不过全 Wa 求助
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_xxxxx_楼主2024/8/12 22:24

qwq,好心人救一下吧。

#include <bits/stdc++.h>
#define int long long
using namespace std;
const int N = 1e5 + 10;
inline int read()
{
	int s = 0, w = 1;
	char ch = getchar();
	while(ch < '0' || ch > '9')
	{
		if(ch == '-') w = -1;
		ch = getchar();
	}
	while(ch >= '0' && ch <= '9')
	{
		s = (s << 3) + (s << 1) + (ch ^ 48);
		ch = getchar();
	}
	return s * w;
}
int n, f, d, s, t;
int head[N], ne[N], to[N], w[N], id = 1;
void add(int x, int y, int z)
{
    to[++id] = y, ne[id] = head[x], w[id] = z, head[x] = id;
    to[++id] = x, ne[id] = head[y], w[id] = 0, head[y] = id;
}
int now[N];
int dis[N];
int q[N], l, r;
void bfs(int s)
{
    memset(dis, -1, sizeof dis);
    dis[q[l = r = 1] = s] = 0;
    while(l <= r)
    {
        int u = q[l++];
        for(int i = head[u]; i; i = ne[i])
        {
            int v = to[i];
            if(w[i] && !~dis[v])
            {
                q[++r] = v;
                dis[v] = dis[u] + 1;
            }
        }
    }
    return ;
}
int dfs(int u, int f)
{
    if(u == t) return f;
    int res = f, t;
    for(int &i = now[u]; i; i = ne[i])
    {
        int v = to[i];
        if(w[i] && dis[v] == dis[u] + 1)
        {
            t = dfs(v, min(res, w[i]));
            if(t)
            {
                w[i] -= t;
                w[i ^ 1] += t;
                res -= t;
                if(!res) break;
            }
            else dis[v] = 0;
        }
    }
    return f - res;
}
int dinic()
{
    int ans = 0, f;
    while(1)
    {
        for(int i = 1; i <= n; i++) now[i] = head[i];
        bfs(s);
        f = dfs(s, 1e18);
        if(!f) return ans;
        ans += f;
    }
    return -1;
}
signed main()
{
    n = read(), f = read(), d = read();
    t = n + n + f + d + 1;
    for(int i = 1; i <= f; i++) add(s, i, 1);
    for(int i = 1; i <= n; i++) add(i + f, i + n + f, 1);
    for(int i = 1; i <= d; i++) add(i + n + n + f, t, 1);
    for(int i = 1; i <= n; i++)
    {
        int fc = read(), dc = read();
        for(int j = 1; j <= fc; j++)
        {
            int x = read();
            add(x, i + f, 1);
        }
        for(int j = 1; j <= dc; j++)
        {
            int x = read();
            add(n + i + f, n + n + x + f, 1);
        }
    }
    printf("%lld\n", dinic());
    return 0;
}
2024/8/12 22:24
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