HDU 2448 Mining Station on the Sea km

#include<cstdio>
#include<string>
#include<cstring>
#include<iostream>
#include<map>
using namespace std;
const int maxn = 105;
const int INF = (1<<30)-1;
int g[2*maxn][2*maxn];
int f[2*maxn][2*maxn];
int lx[maxn],ly[maxn];
int match[maxn];
bool visx[maxn],visy[maxn];
int slack[maxn];
int a[maxn];
int n,m;
bool dfs(int cur){
     visx[cur] = true;
     for(int y=1;y<=n;y++){
         if(visy[y])   continue;
         int t=lx[cur]+ly[y]-g[cur][y];
         if(t==0){
            visy[y] = true;
            if(match[y]==-1||dfs(match[y])){
                match[y] = cur;
                return true;
            }
         }
         else if(slack[y]>t){
                 slack[y]=t;
         }
     }
     return false;
}
int KM(){
    memset(match,-1,sizeof(match));
    memset(ly,0,sizeof(ly));
    for(int i=1 ;i<=n;i++){
         lx[i]=-INF;
       for(int j=1;j<=n;j++)
           if(g[i][j]>lx[i])   lx[i]=g[i][j];
    }
    for(int x=1;x<=n;x++){
        for(int i=1;i<=n;i++)  slack[i]=INF;
        while(true){
            memset(visx,false,sizeof(visx));
            memset(visy,false,sizeof(visy));
            if(dfs(x))  break;
            int d=INF;
            for(int i=1;i<=n;i++){
               if(!visy[i]&&d>slack[i])     d=slack[i];
            }
            for(int i=1;i<=n;i++){
               if(visx[i])                  lx[i]-=d;
            }
            for(int i=1;i<=n;i++){
               if(visy[i])                 ly[i]+=d;
               else                        slack[i]-=d;
            }
        }
   }
    int result = 0;
    for(int i = 1; i <=n ; i++){
      if(match[i]>-1){
        result += g[match[i]][i];
      }
    }
    return result;
}
int main(){
    int val,k,p;
    int x,y,d;
    while(scanf("%d%d%d%d",&n,&m,&k,&p)!=EOF){
        for(int i=1;i<=n;i++)  scanf("%d",&a[i]);

        memset(f,-1,sizeof(f));
        for(int i=0;i<k;i++){
            scanf("%d%d%d",&x,&y,&d);
            f[x][y]=f[y][x]=d;
        }
        for(int i=1;i<=m;i++) f[i][i]=0;

        for(int i=1;i<=n;i++) for(int j=1;j<=n;j++) g[i][j]=INF;

        for(int k=1;k<=m;k++)
           for(int i=1;i<=m;i++)
            for(int j=1;j<=m;j++){
                if(f[i][k]!=-1&&f[k][j]!=-1){
                    int t=f[i][k]+f[k][j];
                    if(f[i][j]==-1||f[i][j]>t){
                       f[i][j]=t;
                    }
                }
            }

            for(int i=0;i<p;i++){
                scanf("%d%d%d",&x,&y,&d);
                for(int j=1;j<=n;j++){
                    int t=(d+f[y][a[j]]);
                   if(t<g[x][j])
                    g[x][j]=t;
                }
            }
            for(int i=1;i<=n;i++) for(int j=1;j<=n;j++)
               g[i][j]=-g[i][j];

        int ans=-KM();

        printf("%d
",ans);
    }
    return 0;
}
原文地址:https://www.cnblogs.com/vermouth/p/3839922.html