Luogu P1646 [国家集训队]happiness(网络流)

版权声明：本文为博主原创文章，未经博主允许必须转载。 https://blog.csdn.net/qq_35950004/article/details/88427318

题目
还是一模一样的套路啊。。。。。。
都不想写博客了。
相异-相同>0，不用反转

AC Code

#include<bits/stdc++.h>
#define maxn 10055
#define maxm maxn * 30
#define inf 0x3f3f3f3f
using namespace std;

char cb[1<<15],*cs=cb,*ct=cb;
#define getc() (cs==ct && (ct = (cs = cb) + fread(cb , 1 , 1<<15 , stdin),cs==ct)?0:*cs++)
void read(int &res)
{
	char ch;bool f=0;
	for(;!isdigit(ch=getc());) if(ch=='-') f=1;
	for(res=ch-'0';isdigit(ch=getc());res=res*10+ch-'0');
	(f) && (res = -res);
}

int n,m,S,T,tot;
int sum[maxn][2],cap[maxm],mark[105][105],a[105][105],b[105][105];
int dis[maxn];
int buf[maxn],info[maxn],Prev[maxm],to[maxm],cnt_e=1;
inline void Node(int u,int v,int c){ Prev[++cnt_e]=info[u],info[u]=cnt_e,to[cnt_e]=v,cap[cnt_e]=c; }
inline void Line(int u,int v,int c,int d=0){ Node(u,v,c),Node(v,u,d); }

int aug(int now,int Max)
{
    if(now == T) return Max;
	int inc , st = Max;
    for(int i=info[now];i;i=Prev[i])
        if(cap[i] && dis[to[i]]+1 == dis[now])
        {
            inc = aug(to[i],min(cap[i] , st));
            if(inc) st -= inc , cap[i] -= inc , cap[i^1] += inc;
			else dis[to[i]] = 0;
            if(!st) break;
        }
    return Max - st;
}

bool BFS()
{
    static queue<int>q;
    memset(dis,-1,sizeof dis);
    q.push(T),dis[T]=0;
    for(int now;!q.empty();)
    {
        now = q.front() , q.pop();
        for(int i=info[now];i;i=Prev[i])
            if(cap[i^1] && dis[to[i]]==-1)
            {
                dis[to[i]] = dis[now] + 1;
                q.push(to[i]);
            }
    }
    return dis[S] != -1;
}

int main()
{
	scanf("%d%d",&n,&m);
	int ans = 0 , x;
	for(int i=1;i<=n;i++)
		for(int j=1;j<=m;j++)
			mark[i][j] = ++tot;
	for(int i=1;i<=n;i++)
		for(int j=1;j<=m;j++)
		{
			scanf("%d",&x);x*=2;
			sum[mark[i][j]][1] += x;
			ans += x;
		}
	for(int i=1;i<=n;i++)
		for(int j=1;j<=m;j++)
		{
			scanf("%d",&x);x*=2;
			sum[mark[i][j]][0] += x;
			ans += x;
		}
	for(int i=1;i<n;i++)
		for(int j=1;j<=m;j++)
			scanf("%d",&a[i][j]),a[i][j]<<=1,ans+=a[i][j];
	for(int i=1;i<n;i++)
		for(int j=1;j<=m;j++)
			scanf("%d",&b[i][j]),b[i][j]<<=1,ans+=b[i][j];
	for(int i=1;i<n;i++)
		for(int j=1;j<=m;j++)
		{
			sum[mark[i][j]][1] += a[i][j]/2;
			sum[mark[i+1][j]][1] += a[i][j]/2;
			sum[mark[i][j]][0] += b[i][j]/2;
			sum[mark[i+1][j]][0] += b[i][j]/2;
			Line(mark[i][j],mark[i+1][j],(a[i][j]+b[i][j])/2,(a[i][j]+b[i][j])/2);
		}
	for(int i=1;i<=n;i++)
		for(int j=1;j<m;j++)
			scanf("%d",&a[i][j]),a[i][j]<<=1,ans+=a[i][j];
	for(int i=1;i<=n;i++)
		for(int j=1;j<m;j++)
			scanf("%d",&b[i][j]),b[i][j]<<=1,ans+=b[i][j];
	for(int i=1;i<=n;i++)
		for(int j=1;j<m;j++)
		{
			sum[mark[i][j]][1] += a[i][j]/2;
			sum[mark[i][j+1]][1] += a[i][j]/2;
			sum[mark[i][j]][0] += b[i][j]/2;
			sum[mark[i][j+1]][0] += b[i][j]/2;
			Line(mark[i][j],mark[i][j+1],(a[i][j]+b[i][j])/2,(a[i][j]+b[i][j])/2);
		}
	S = ++tot , T = ++tot;
	for(int i=1;i<=mark[n][m];i++)
		Line(S,i,sum[i][0]),
		Line(i,T,sum[i][1]);
	
    for(;BFS();)
	{
        ans -= aug(S,inf);
	}
    printf("%d\n",ans/2);
}