OJ-Problems-Source/HDOJ/1689_autoAC.cpp

73 lines
1.6 KiB
C++
Raw Normal View History

#include<iostream>
#include<vector>
#include<queue>
#include<cstring>
#define maxn 10000+1
using namespace std;
vector<int>mapp[maxn];
int n,m;
int visit[maxn][2];
struct stu
{
int pre;
int now;
int deep;
};
int bfs(int p)
{
queue<stu>root;
stu x,y;
x.pre=-1;
x.now=p;
x.deep=0;
root.push(x);
while(root.size())
{
x=root.front();
root.pop();
if(x.now==p&&x.deep>=3&&x.deep%2) return x.deep;
else if(x.now==p&&x.deep!=0) continue;
for(int i=0;i<mapp[x.now].size();i++)
{
if(mapp[x.now][i]!=x.pre&&!visit[mapp[x.now][i]][(x.deep+1)%2])
{
y.pre=x.now;
y.now=mapp[x.now][i];
y.deep=x.deep+1;
visit[y.now][y.deep%2]=1;
root.push(y);
}
}
}
return 1<<30;
}
int main()
{
cin.sync_with_stdio(false);
int t;
cin>>t;
int casee=1;
while(t--)
{
cin>>n>>m;
for(int i=1;i<=n;i++) mapp[i].clear();
for(int i=0;i<m;i++)
{
int x,y;
cin>>x>>y;
mapp[x].push_back(y);
mapp[y].push_back(x);
}
int ans=1<<30;
for(int i=1;i<=n;i++)
{
memset(visit,0,sizeof(visit));
ans=min(ans,bfs(i));
}
cout<<"Case "<<casee++<<": ";
if(ans!=1<<30) cout<<"JYY has to use "<<ans<<" balls."<<endl;
else cout<<"Poor JYY."<<endl;
}
return 0;
}