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hdu-4322-Candy-费用流

2014-02-15 10:29 309 查看
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#include<cstdio>
#include<cstring>
#include<iostream>
#include<cstdlib>
#include<algorithm>
using namespace std;

const int N = 1010;//点
const int M = 2 * 10010;//边
const int inf = 1000000000;
struct Node{//边,点f到点t,流量为c,费用为w
int f, t, c, w;
}e[M];
int next1[M], point
, dis
, q
, pre
, ne;//ne为已添加的边数,next,point为邻接表,dis为花费,pre为父亲节点
bool u
;
void init(){
memset(point, -1, sizeof(point));
ne = 0;
}
void add_edge(int f, int t, int d1, int d2, int w){//f到t的一条边,流量为d1,反向流量d2,花费w,反向边花费-w(可以反悔)
e[ne].f = f, e[ne].t = t, e[ne].c = d1, e[ne].w = w;
next1[ne] = point[f], point[f] = ne++;
e[ne].f = t, e[ne].t = f, e[ne].c = d2, e[ne].w = -w;
next1[ne] = point[t], point[t] = ne++;
}
bool spfa(int s, int t, int n){
int i, tmp, l, r;
memset(pre, -1, sizeof(pre));
for(i = 0; i < n; ++i)
dis[i] = inf;
dis[s] = 0;
q[0] = s;
l = 0, r = 1;
u[s] = true;
while(l != r) {
tmp = q[l];
l = (l + 1) % (n + 1);
u[tmp] = false;
for(i = point[tmp]; i != -1; i = next1[i]) {
if(e[i].c && dis[e[i].t] > dis[tmp] + e[i].w) {
dis[e[i].t] = dis[tmp] + e[i].w;
pre[e[i].t] = i;
if(!u[e[i].t]) {
u[e[i].t] = true;
q[r] = e[i].t;
r = (r + 1) % (n + 1);
}
}
}
}
if(pre[t] == -1)
return false;
return true;
}
void MCMF(int s, int t, int n, int &flow, int &cost){//起点s,终点t,点数n,最大流flow,最小花费cost
int tmp, arg;
flow = cost = 0;
while(spfa(s, t, n)) {
arg = inf, tmp = t;
while(tmp != s) {
arg = min(arg, e[pre[tmp]].c);
tmp = e[pre[tmp]].f;
}
tmp = t;
while(tmp != s) {
e[pre[tmp]].c -= arg;
e[pre[tmp] ^ 1].c += arg;
tmp = e[pre[tmp]].f;
}
flow += arg;
cost += arg * dis[t];
}
}
//建图前运行init()
//节点下标从0开始
//加边时运行add_edge(a,b,c,0,d)表示加一条a到b的流量为c花费为d的边(注意花费为单位流量花费)
//特别注意双向边,运行add_edge(a,b,c,0,d),add_edge(b,a,c,0,d)较好,不要只运行一次add_edge(a,b,c,c,d),费用会不对。
//求解时代入MCMF(s,t,n,v1,v2),表示起点为s,终点为t,点数为n的图中,最大流为v1,最大花费为v2

int map[15][15];
int b[15];
int main()
{
int t;
cin>>t;
int ans=0;
while(t--)
{
ans++;
int n,m,k,i,j,sum=0;
cin>>n>>m>>k;
for(i=1;i<=m;i++) {
cin>>b[i];
sum+=b[i];
}
for(i=1;i<=m;i++)
for(j=1;j<=n;j++)
cin>>map[i][j];
init();
for(i=1;i<=n;i++)
add_edge(0,i,1,0,0);
for(i=1;i<=m;i++){
for(j=1;j<=n;j++)
{
if(map[i][j]==1)
{
add_edge(j,i+n,1,0,0);
}
}
add_edge(i+n,n+m+1,b[i]/k,0,-k);
if(b[i]%k>1)
add_edge(i+n,n+m+1,1,0,-(b[i]%k));
}
int flow,cost;
MCMF(0,n+m+1,n+m+2,flow,cost);
if(n-flow>=sum+cost)
cout<<"Case #"<<ans<<": "<<"YES"<<endl;
else
cout<<"Case #"<<ans<<": "<<"NO"<<endl;
}
}
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