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Time Limit: 10000/1000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others)
Total Submission(s): 1523 Accepted Submission(s): 616
#include<iostream>
#include<cstdio>
#include<cstring>
#include<string>
#include<cmath>
#include<cstdlib>
#include<algorithm>
#include<queue>
#include<stack>
#include<set>
#include<map>
using namespace std;
stack<int> s;
vector<int> e[7010];
int n,m,Dfs[7010],use[7010],low[7010],isstack[7010];
int top,newflag;
void init()
{
memset(Dfs,0,sizeof(Dfs));
memset(use,0,sizeof(use));
memset(low,0,sizeof(low));
memset(isstack,0,sizeof(isstack));
top=0,newflag=0;
for(int i=1;i<=6*n;i++)
e[i].clear();
while(!s.empty())
s.pop();
}
void tarjan(int u)
{
Dfs[u]=low[u]=++top;
isstack[u]=1;
s.push(u);
for(int i=0;i<e[u].size();i++)
{
int v=e[u][i];
if(!Dfs[v])
{
tarjan(v);
low[u]=min(low[u],low[v]);
}
else if(isstack[v])
low[u]=min(low[u],Dfs[v]);
}
if(Dfs[u]==low[u])
{
newflag++;
int x;
do
{
x=s.top();
s.pop();
isstack[x]=0;
use[x]=newflag;
}while(x!=u);
}
}
int main()
{
while(scanf("%d%d",&n,&m)!=EOF)
{
init();
for(int i=1;i<=n;i++)
{
int a,b,c;
scanf("%d%d%d",&a,&b,&c);
a++,b++,c++;
e[a+3*n].push_back(b);
e[a+3*n].push_back(c);
e[b+3*n].push_back(a);
e[c+3*n].push_back(a);
}
for(int i=1;i<=m;i++)
{
int a,b;
scanf("%d%d",&a,&b);
a++,b++;
e[a].push_back(b+3*n);
e[b].push_back(a+3*n);
}
for(int i=1;i<=6*n;i++)
{
if(!Dfs[i])
tarjan(i);
}
bool flag=true;
for(int i=1;i<=6*n;i++)
{
if(use[i]==use[i+n])
{
flag=false;
break;
}
}
if(flag)
printf("yes\n");
else
printf("no\n");
}
return 0;
}
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原文地址:http://www.cnblogs.com/water-full/p/4531578.html