KM(n^3)模板

#include<iostream>
#include<cstdio>
#include<cmath>
#include<cstring>

using namespace std;

#define REP(i,a,b) for(register int i = (a), i##_end_ = (b); i <= i##_end_ ; ++i)

const int maxn = 310;

const int oo = 0x3f3f3f3f;

int n,m,ans,lack,v[maxn][maxn],lx[maxn],ly[maxn],par[maxn],slack[maxn];

bool vx[maxn],vy[maxn];

bool dfs(int x)
{
	vx[x] = 1;
	REP(i,1,n)
	{
		if(vy[i])continue;
		int t = lx[x] + ly[i] - v[x][i];
		if(!t)
		{
			vy[i] = 1;
			if(par[i] == -1 || dfs(par[i]))
			{
				par[i] = x;
				return 1;
			}
		}
		else slack[i] = min(slack[i], t);
	}
	return 0;
}

void km()
{
	memset(par,-1,sizeof(par));
	REP(i,1,n)
	{
		REP(j,1,n) slack[j] = oo;
		while(1) 
		{
			memset(vx,0,sizeof(vx));
			memset(vy,0,sizeof(vy));
			if(dfs(i))break;
			int dx = oo;
			REP(j, 1, n)
				if(!vy[j] && slack[j] < dx)
					dx = slack[j];
			REP(j, 1, n)
				if(vx[j])
					lx[j] -= dx;
			REP(j, 1, n)
				if(vy[j])
					ly[j] += dx;
				else slack[j] -= dx;
		}
	}
}

int main()
{
	while(scanf("%d",&n)!=EOF)
	{
		ans = 0;
		memset(lx,0,sizeof(lx));
		memset(ly,0,sizeof(ly));
		memset(slack, 0x3f, sizeof slack);
		REP(i, 1, n)
			REP(j,1, n)
			{
				scanf("%d",&v[i][j]);
				lx[i] = max(v[i][j], lx[i]);
			}
		km();
		REP(i,1,n)ans += v[par[i]][i];
		printf("%d\n",ans);
	}
	return 0;
}