//1.联通图 2.顶点度数都为偶数 ,则存在欧拉回路。
# include <stdio.h>
# include <algorithm>
# include <string.h>
using namespace std;
int father[1010];
int vis[1010][1010],du[1010];
int find(int x)
{
if(father[x]==x)
return x;
return father[x]=find(father[x]);
}
int main()
{
int n,m,i,a,b,cot;
while(~scanf("%d",&n),n)
{
for(i=1;i<=n;i++)
father[i]=i;
scanf("%d",&m);
memset(vis,0,sizeof(vis));
memset(du,0,sizeof(du));
while(m--)
{
scanf("%d%d",&a,&b);
if(!vis[a][b])
{
if(a>b)
swap(a,b);//小的前面,保证父亲节点为最小的那个
vis[a][b]=vis[b][a]=1;
du[a]++;
du[b]++;
int fa=find(a);
int fb=find(b);
if(fa!=fb)
{
father[fb]=fa;
}
}
}
cot=0;
for(i=1;i<=n;i++)
{
if(du[i]%2==0&&find(i)==1)
{
cot++;
}
}
if(cot==n)
printf("1\n");
else
printf("0\n");
}
return 0;
}
hdu 1878 欧拉回路 (欧拉回路),布布扣,bubuko.com
原文地址:http://blog.csdn.net/lp_opai/article/details/38467399