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#include <cstdio>
#include <cstring>
#include <iostream>
#include <algorithm>
using namespace std;

const int maxn=333;
const int oo=0x3f3f3f3f;

int maps[maxn][maxn],lx[maxn],ly[maxn];
int visx[maxn],visy[maxn],s[maxn],used[maxn],n;

bool finds(int u)
{
    visx[u]=1;
    for(int i=1;i<=n;i++)
    {
        if(!visy[i]&&lx[u]+ly[i]==maps[u][i])
        {
            visy[i]=1;
            if(!used[i]||finds(used[i]))//如果used[i]没有被占用  或者 被占用但是used[i]可以被让出来  返回真;
            {
                used[i]=u;
                return true;
            }
        }
        else//不满足则更新d;
        {
            s[i]=min(s[i],lx[u]+ly[i]-maps[u][i]);
        }
    }
    return false;
}
int km()
{
    memset(used,0,sizeof(used));
    memset(lx,0,sizeof(lx));
    memset(ly,0,sizeof(ly));
    for(int i=1;i<=n;i++)
    {
        for(int j=1;j<=n;j++)
        {
            lx[i]=max(lx[i],maps[i][j]);
        }
    }
    for(int i=1;i<=n;i++)
    {
        for(int j=1;j<=n;j++)
        {
            s[j]=oo;
        }
        while(1)
        {
            memset(visx,0,sizeof(visx));
            memset(visy,0,sizeof(visy));
            if(finds(i))//如果找到增广路,退出 否则更新d继续寻找;
                break;
            int d=oo;
            for(int j=1;j<=n;j++)
            {
                if(!visy[j])
                {
                    d=min(d,s[j]);
                }
            }
            for(int j=1;j<=n;j++)//如果在增光路中  则作出相应变化
            {
                if(visx[j])
                    lx[j]-=d;
                if(visy[j])
                    ly[j]+=d;
            }
        }
    }
    int res=0;
    for(int i=1;i<=n;i++)
    {
        res+=maps[used[i]][i];
    }
    return res;
}

int main()
{
    while(scanf("%d",&n)!=EOF)
    {
        for(int i=1;i<=n;i++)
        {
            for(int j=1;j<=n;j++)
            {
                scanf("%d",&maps[i][j]);
            }
        }
        printf("%d ",km());
    }
    return 0;
}

原文地址:https://www.cnblogs.com/mengzhong/p/4713775.html