Rt.

又是P3376，只不过换成了dicnic

本地和洛谷测了样例和测试数据 $1$ 都没问题，但评测全 R E

代码如下：

#include <cstdio>
#include <cstring>
#include <queue>

using namespace std;

struct edge
{
	int next, to;
	long long w;
};

int n, m, s, t, cur = 1, dis[2005], head[2005];
long long w, x, y, ans;
queue<int> q;
edge e[100005];

int add(int u, int v, long long w)
{
	++cur;
	e[cur] = {head[u], v, w};
	head[u] = cur;
}

bool bfs()
{
	while (!q.empty())
	{
		q.pop();
	}
	q.push(s);
	memset(dis, 0, sizeof(dis));
	dis[s] = 1;
	while (!q.empty())
	{
		x = q.front();
		q.pop();
		for (register int i = head[x]; i; i = e[i].next)
		{
			y = e[i].to;
			if (dis[y] || e[i].w == 0)
			{
				continue;
			}
			q.push(y);
			dis[y] = dis[x] + 1;
			if (y == t)
			{
				return true;
			}
		}
	}
	return false;
}

long long dicnic(int u, long long flow)
{
	if (u == t)
	{
		return flow;
	}
	long long sum = 0;
	for (register int i = head[u]; i; i = e[i].next)
	{
		x = e[i].to;
		if (dis[x] != dis[u] + 1 || e[i].w == 0)
		{
			continue;
		}
		y = dicnic(x, min(flow, e[i].w));
		e[i].w -= y;
		e[i ^ 1].w += y;
		flow -= y;
		sum += y;
		if (flow == 0)
		{
			break;
		}
	}
	return sum;
}

int main()
{
	scanf("%d%d%d%d", &n, &m, &s, &t);
	while (m--)
	{
		scanf("%d%d%lld", &x, &y, &w);
		add(x, y, w);
		add(y, x, 0);
	}
	while (bfs())
	{
		ans += dicnic(s, 1e18);
	}
	printf("%lld", ans);
	return 0;
}

若有大佬救我，我定将感激不尽！