MCMF最大流最小割（模板）Dijkstra负权优化

#define IOS ios_base::sync_with_stdio(0); cin.tie(0);
#include <cstdio>//sprintf islower isupper
#include <cstdlib>//malloc  exit strcat itoa system("cls")
#include <iostream>//pair
#include <fstream>//freopen("C:\Users\13606\Desktop\Input.txt","r",stdin);
#include <bitset>
//#include <map>
//#include<unordered_map>
#include <vector>
#include <stack>
#include <set>
#include <string.h>//strstr substr
#include <string>
#include <time.h>// srand(((unsigned)time(NULL))); Seed n=rand()%10 - 0~9;
#include <cmath>
#include <deque>
#include <queue>//priority_queue<int, vector<int>, greater<int> > q;//less
#include <vector>//emplace_back
//#include <math.h>
#include <cassert>
//#include <windows.h>//reverse(a,a+len);// ~ ! ~ ! floor
#include <algorithm>//sort + unique : sz=unique(b+1,b+n+1)-(b+1);+nth_element(first, nth, last, compare)
using namespace std;//next_permutation(a+1,a+1+n);//prev_permutation
//******************
int abss(int a);
int lowbit(int n);
int Del_bit_1(int n);
int maxx(int a,int b);
int minn(int a,int b);
double fabss(double a);
void swapp(int &a,int &b);
clock_t __STRAT,__END;
double __TOTALTIME;
void _MS(){__STRAT=clock();}
void _ME(){__END=clock();__TOTALTIME=(double)(__END-__STRAT)/CLOCKS_PER_SEC;cout<<"Time: "<<__TOTALTIME<<" s"<<endl;}
//***********************
#define rint register int
#define fo(a,b,c) for(rint a=b;a<=c;++a)
#define fr(a,b,c) for(rint a=b;a>=c;--a)
#define mem(a,b) memset(a,b,sizeof(a))
#define pr printf
#define sc scanf
#define ls rt<<1
#define rs rt<<1|1
typedef pair<int,int> PII;
typedef vector<int> VI;
typedef long long ll;
const double E=2.718281828;
const double PI=acos(-1.0);
//const ll INF=(1LL<<60);
const int inf=(1<<30);
const double ESP=1e-9;
const int mod=(int)1e9+7;
const int N=(int)1e5+10;

int n,m,S,T;
class MCMF
{
public:
    struct node
    {
        int u,v,f,w,nxt;
    }edge[N];
    int head[N],tot;
    int h[N],dis[N],PrePoint[N],PreEdge[N];
    void Init(int n)
    {
        tot=-1;
        for(int i=0;i<=n;++i)
            head[i]=-1,h[i]=0;
    }
    void add(int x,int y,int f,int w)
    {
        ++tot;
        edge[tot]={x,y,f,w,head[x]};
        head[x]=tot;
    }
    void Add(int x,int y,int f,int w)
    {
        add(x,y,f,w);
        add(y,x,0,-w);
    }
    PII Dij()
    {
        int max_flow=0,min_cost=0;
        while(1)
        {
            priority_queue<PII>q;
            for(int i=1;i<=n;++i)
                dis[i]=inf;
            dis[S]=0;
            q.push({0,S});
            while(!q.empty())
            {
                PII now=q.top();q.pop();
                if(-now.first!=dis[now.second])continue;
                if(now.second==T)break;
                for(int i=head[now.second];i!=-1;i=edge[i].nxt)
                {
                    int nowcost=edge[i].w+h[now.second]-h[edge[i].v];
                    if(edge[i].f>0&&dis[edge[i].v]>dis[now.second]+nowcost)
                    {
                        dis[edge[i].v]=dis[now.second]+nowcost;
                        q.push({-dis[edge[i].v],edge[i].v});
                        PrePoint[edge[i].v]=now.second;
                        PreEdge[edge[i].v]=i;
                    }
                }
            }
            if(dis[T]==inf)break;
            for(int i=0;i<=n;++i)h[i]+=dis[i];
            int nowflow=inf;
            for(int i=T;i!=S;i=PrePoint[i])
                nowflow=min(nowflow,edge[PreEdge[i]].f);
            for(int i=T;i!=S;i=PrePoint[i])
            {
                edge[PreEdge[i]].f-=nowflow;
                edge[PreEdge[i]^1].f+=nowflow;
            }
            max_flow+=nowflow;
            min_cost+=nowflow*h[T];
        }
        return {max_flow,min_cost};
    }
}G;

char mp[103][103];
int id[103][103];

int main()
{
    int h,l;
    while(sc("%d%d",&h,&l),h&&l)
    {
        S=h*l+1,T=h*l+2;
        int cnt=0;
        fo(i,1,h)
            fo(j,1,l)
                sc("%1s",&mp[i][j]),id[i][j]=++cnt;
        n=h*l+2;
        G.Init(n);
        for(int i=1;i<=h;++i)
        {
            for(int j=1;j<=l;++j)
            {
                if(i>1)G.Add(id[i][j],id[i-1][j],inf,1);
                if(j>1)G.Add(id[i][j],id[i][j-1],inf,1);
                if(i<h)G.Add(id[i][j],id[i+1][j],inf,1);
                if(j<l)G.Add(id[i][j],id[i][j+1],inf,1);
                if(mp[i][j]=='m')G.Add(S,id[i][j],1,0);
                if(mp[i][j]=='H')G.Add(id[i][j],T,1,0);
            }
        }
        PII ans=G.Dij();
        pr("%d
",ans.second);
    }
    return 0;
}

/**************************************************************************************/

int maxx(int a,int b)
{
    return a>b?a:b;
}

void swapp(int &a,int &b)
{
    a^=b^=a^=b;
}

int lowbit(int n)
{
    return n&(-n);
}

int Del_bit_1(int n)
{
    return n&(n-1);
}

int abss(int a)
{
    return a>0?a:-a;
}

double fabss(double a)
{
    return a>0?a:-a;
}

int minn(int a,int b)
{
    return a<b?a:b;
}