# hdu 2448 Mining Station on the Sea (floyd+KM)

Posted by 111qqz on Thursday, June 2, 2016

## TOC

hdu2448 题目链接

``````/* ***********************************************
Author :111qqz
Created Time :2016年06月03日 星期五 03时07分16秒
File Name :code/hdu/2448.cpp
************************************************ */

#include <cstdio>
#include <cstring>
#include <iostream>
#include <algorithm>
#include <vector>
#include <queue>
#include <set>
#include <map>
#include <string>
#include <cmath>
#include <cstdlib>
#include <ctime>
#define fst first
#define sec second
#define lson l,m,rt<<1
#define rson m+1,r,rt<<1|1
#define ms(a,x) memset(a,x,sizeof(a))
typedef long long LL;
#define pi pair < int ,int >
#define MP make_pair

using namespace std;
const double eps = 1E-8;
const int dx4[4]={1,0,0,-1};
const int dy4[4]={0,-1,1,0};
const int inf = 0x3f3f3f3f;
const int N=205;
int n,m,k,p;
int id[N];
int a[N][N],b[N][N];
int lx[N],ly[N];
bool visx[N],visy[N];
int slk[N];
int w[N][N];

bool find( int u)
{
//   cout<<"u:"<<u<<endl;
visx[u] = true;

for ( int v = 1 ; v <= n ; v++)
{
if (visy[v]) continue;
int tmp = lx[u] + ly[v] - w[u][v];
if (tmp==0)
{
visy[v] = true;
{
return true;
}
}else if(tmp<slk[v]) slk[v] = tmp;
}
return false;
}
LL KM()
{
ms(lx,0xc0);
ms(ly,0);

for ( int i = 1 ; i <= n ; i++)
for ( int j =  1 ; j <= n ; j++)
lx[i] = max(lx[i],w[i][j]);

for ( int i = 1 ; i <= n ; i++)
{
ms(slk,0x3f);

while (1)
{
ms(visx,false);
ms(visy,false);

if (find(i)) break;

int d = inf;

for ( int j = 1 ; j <= n ; j++)
if (!visy[j]&&slk[j]<d) d = slk[j];

for ( int j = 1 ; j <= n ; j++)
if (visx[j]) lx[j]-=d;
for ( int j = 1 ; j <= n ; j++)
if (visy[j]) ly[j]+=d ; else slk[j]-=d;
}
}
LL res = 0LL ;

for ( int i= 1 ; i <= n ; i++)

return -res;

}
int main()
{
#ifndef  ONLINE_JUDGE
freopen("code/in.txt","r",stdin);
#endif

while (scanf("%d%d%d%d",&n,&m,&k,&p)!=EOF)
{
ms(a,0x3f);
ms(b,0x3f);
ms(id,0);
ms(w,0x3f);
for ( int i = 1 ;i <= m ; i++) a[i][i] = 0 ;
for ( int i = 1 ; i <= n ; i++) scanf("%d",&id[i]);

for ( int i = 1 ; i <= k ; i++)
{
int u,v,cost;
scanf("%d%d%d",&u,&v,&cost);
//a[u][v] = max(a[u][v],-w);
a[u][v] = min(a[u][v],cost);
a[v][u] = min(a[v][u],cost);
}

for ( int kk = 1 ; kk <= m ; kk++)
for ( int i = 1 ; i <= m ; i++)
for ( int j = 1 ; j <= m ; j++)
a[i][j] = min(a[i][j],a[i][kk]+a[kk][j]);
for ( int i = 1 ; i <= p ; i++)
{
int u,v,cost;
scanf("%d%d%d",&u,&v,&cost);
for ( int j = 1 ; j <= n ; j++)
w[j][u] = min(w[j][u],a[id[j]][v]+cost);
}

//	    for ( int kk = 1 ; kk <= m ; kk++)  //这只是港口经过中间station到达station的距离近了，还有station经过中间station到达station距离近的情况没考虑,必须放在一起更新。
//		for ( int i = 1 ; i <= n ; i++)
//		    for ( int j = 1 ; j <= m ; j++)
//			if (b[i][kk]+a[kk][j]<b[i][j]) b[i][j] = b[i][kk] + a[kk][j];

for ( int i = 1 ; i <= n ; i++)
for ( int j = 1 ; j <= n ; j++)
w[i][j]=-w[i][j];

LL ans = KM();
printf("%lld\n",ans);

}

#ifndef ONLINE_JUDGE
fclose(stdin);
#endif
return 0;
}
``````

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