You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
89 lines
2.3 KiB
C++
89 lines
2.3 KiB
C++
#include <cstdio>
|
|
#include <cstring>
|
|
#include <cmath>
|
|
#include <algorithm>
|
|
using namespace std;
|
|
const int inf = 0x3f3f3f3f, N = 10005, M = 100005;
|
|
int adj[N], nxt[M], to[M], cap[M], ecnt, idx;
|
|
double dis[N], cost[M];
|
|
inline void addEdge_impl_(int f, int t, int c, double w)
|
|
{
|
|
nxt[ecnt] = adj[f];
|
|
adj[f] = ecnt;
|
|
to[ecnt] = t;
|
|
cap[ecnt] = c;
|
|
cost[ecnt] = w;
|
|
ecnt++;
|
|
}
|
|
inline void addEdge(int f, int t, int c, double w)
|
|
{
|
|
addEdge_impl_(f, t, c, w);
|
|
addEdge_impl_(t, f, 0, -w);
|
|
}
|
|
int END;
|
|
bool bfs(int S)
|
|
{
|
|
memset(dis, 0x7f, sizeof(dis)), idx++;
|
|
static int que[N << 1];
|
|
static bool inq[N];
|
|
int len = 0;
|
|
dis[que[len++] = S] = 0;
|
|
for (int i = 0; i < len; inq[que[i++]] = false)
|
|
for (int e = adj[que[i]]; ~e; e = nxt[e])
|
|
if (cap[e] && (dis[to[e]] - dis[que[i]] - cost[e])>1e-8)
|
|
{
|
|
dis[to[e]] = dis[que[i]] + cost[e];
|
|
if (!inq[to[e]])
|
|
que[len++] = to[e];
|
|
}
|
|
return dis[END] < inf;
|
|
}
|
|
int dfs(int x, int rest)
|
|
{
|
|
static int vis[N];
|
|
if (x == END)
|
|
return rest;
|
|
vis[x] = idx;
|
|
int flow = 0;
|
|
for (int e = adj[x], curFlow; rest && ~e; e = nxt[e])
|
|
if (vis[to[e]] != idx && cap[e] && abs(dis[to[e]] - dis[x] - cost[e])<1e-8)
|
|
if (bool(curFlow = dfs(to[e], min(cap[e], rest))))
|
|
rest -= curFlow, flow += curFlow, cap[e] -= curFlow,
|
|
cap[e ^ 1] += curFlow;
|
|
return flow;
|
|
}
|
|
int main()
|
|
{
|
|
int T,n,m;
|
|
scanf("%d",&T);
|
|
while(T--)
|
|
{
|
|
memset(adj, -1, sizeof(adj));
|
|
ecnt=0;
|
|
scanf("%d%d",&n,&m);
|
|
END=n+1;
|
|
for(int i=1,a,b,c; i<=n; i++)
|
|
{
|
|
scanf("%d%d",&a,&b),c=a-b;
|
|
if(c>0)
|
|
addEdge(0,i,c,0);
|
|
if(c<0)
|
|
addEdge(i,n+1,-c,0);
|
|
}
|
|
double p;
|
|
for(int i=0,u,v,f; i<m; i++)
|
|
{
|
|
scanf("%d%d%d%lf",&u,&v,&f,&p);
|
|
if(f>0)
|
|
addEdge(u,v,1,0);
|
|
if(f>1)
|
|
addEdge(u,v,f-1,-log(1-p));
|
|
}
|
|
double ans=0;
|
|
while (bfs(0))
|
|
ans += dis[n+1] * dfs(0, inf);
|
|
printf("%.2f\n",1-exp(-ans));
|
|
}
|
|
return 0;
|
|
}
|