题目链接
http://poj.org/problem?id=1459
这道题我想用scanf输入坑死,,,最后老老实实用cin做了,,,
后来网上学了下其实用scanf(“% * ^(“);scanf(“(%d,%d)%d”, &a, &b, &c);就可以。scanf(“%*^(“);的意思是读入一行字符串直到遇到(字符,并且不读入(字符。
#include <iostream>
#include <cstdio>
#include <cstring>
#include <queue>
#include <vector>
using namespace std;
const int maxn = 150;
const int INF = 0x3f3f3f3f;
struct Edge
{
int from, to, cap, flow;
Edge(int u, int v, int c, int f) : from(u), to(v), cap(c), flow(f){}
};
struct EdmondsKarp
{
vector<int>G[maxn];
vector<Edge>edges;
int a[maxn];
int p[maxn];
void init(int n)
{
for(int i = 0;i <= n + 2;i++)
{
G[i].clear();
}
edges.clear();
}
void AddEdge(int from, int to, int cap)
{
edges.push_back(Edge(from, to, cap, 0));
edges.push_back(Edge(to, from, 0, 0));
int m = edges.size();
G[from].push_back(m - 2);
G[to].push_back(m - 1);
}
int MaxFlow(int s, int t)
{
int flow = 0;
for(;;)
{
memset(a, 0, sizeof(a));
queue<int>Q;
Q.push(s);
a[s] = INF;
while(!Q.empty())
{
int x = Q.front();
Q.pop();
for(int i = 0;i < (int)G[x].size();i++)
{
Edge &e = edges[G[x][i]];
if(!a[e.to]&&e.cap - e.flow > 0)
{
p[e.to] = G[x][i];
a[e.to] = min(a[x], e.cap - e.flow);
Q.push(e.to);
}
}
if(a[t])
break;
}
if(!a[t])
break;
for(int u = t;u != s;u = edges[p[u]].from)
{
edges[p[u]].flow += a[t];
edges[p[u]^1].flow -= a[t];
}
flow += a[t];
}
return flow;
}
}ek;
int main()
{
int n, np, nc, m;
while(cin>>n>>np>>nc>>m)
{
ek.init(n);
for(int i = 1;i <= m;i++)
{
int a, b, c;
char ch;
cin>>ch>>a>>ch>>b>>ch>>c;
ek.AddEdge(a, b, c);
}
for(int i = 1;i <= np;i++)
{
int a, b;
char ch;
cin>>ch>>a>>ch>>b;
ek.AddEdge(n + 1, a, b);
}
for(int i = 1;i <= nc;i++)
{
int a, b;
char ch;
cin>>ch>>a>>ch>>b;
ek.AddEdge(a, n + 2, b);
}
cout<<ek.MaxFlow(n + 1, n + 2)<<endl;
}
return 0;
}