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hdu3472 HS BDC --- 混合圖歐拉回路

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hdu3472 HS BDC --- 混合圖歐拉回路

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#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#define inf 0x3f3f3f3f
#pragma comment(linker, "/STACK:16777216")
#define eps 1e-6
#define ll long long
using namespace std;
const int maxn=30;

struct node
{
    int from,to,cap,flow;
};
struct dinic
{
    int n,m,s,t;
    vector e;
    vector g[maxn];
    bool vis[maxn];
    int d[maxn];
    int cur[maxn];

    void init(int n)
    {
        e.clear();
        for(int i=0;i<=n+2;i++)
            g[i].clear();
    }

    void addedge(int a,int b,int c,int d)
    {
        e.push_back((node){a,b,c,0});
        e.push_back((node){b,a,d,0});
        m=e.size();
        g[a].push_back(m-2);
        g[b].push_back(m-1);
    }

    bool bfs()
    {
        memset(vis,0,sizeof vis);
        queue q;
        q.push(s);
        d[s]=0;
        vis[s]=1;
        while(!q.empty())
        {
            int x=q.front();q.pop();
            for(int i=0;iee.flow)
                {
                    vis[ee.to]=1;
                    d[ee.to]=d[x]+1;
                    q.push(ee.to);
                }
            }
        }
        return vis[t];
    }

    int dfs(int x,int a)
    {
        if(x==t||a==0) return a;
        int flow=0,f;
        for(int& i=cur[x];i0)
            {
                ee.flow+=f;
                e[g[x][i]^1].flow-=f;
                flow+=f;
                a-=f;
                if(a==0) break;
            }
        }
        return flow;
    }

    int maxflow(int s,int t)
    {
        this->s=s;
        this->t=t;
        int flow=0;
        while(bfs())
        {
            memset(cur,0,sizeof cur);
            flow+=dfs(s,inf);
        }
        return flow;
    }
};
dinic solve;

int r[30],vis[30],in[30],out[30];
int root(int a)
{
    if(r[a]==-1) return a;
    return r[a]=root(r[a]);
}
void merge(int a,int b)
{
    int ra=root(a);
    int rb=root(b);
    if(ra!=rb) r[ra]=rb;
}

int main()
{
    char s[22];
    int T,a,i,n,u,v,j,d,tmp,cas=1;
    scanf("%d",&T);
    while(T--)
    {
        scanf("%d",&n);
        solve.init(26);
        memset(in,0,sizeof in);
        memset(out,0,sizeof out);
        memset(vis,0,sizeof vis);
        memset(r,-1,sizeof r);
        for(i=0;i0&&d%2) v=i,tmp++;
            if(tmp>2) flag=0;
        }
        if(!flag)
        {
            printf("Case %d: Poor boy!\n",cas++);
            continue;
        }
        if(tmp==2) solve.addedge(u,v,1,0);
        int sum=0;
        for(i=0;i<26;i++)
        {
            d=in[i]-out[i];
            if(d<0) solve.addedge(26,i,-d/2,0);
            else if(d>0)
            {
                solve.addedge(i,27,d/2,0);
                sum+=d/2;
            }
        }
        tmp=solve.maxflow(26,27);
      // printf("sum:%d flow:%d\n",sum,tmp);
        if(tmp!=sum)
            printf("Case %d: Poor boy!\n",cas++);
        else printf("Case %d: Well done!\n",cas++);
    }
    return 0;
}