#include <iostream>
#include <fstream>
using namespace std;
ifstream fin("graf.in");
int a[100][100],viz[100],n,ok=1;
void citire()
{
    int i,j;
    fin>>n;
    while(fin>>i>>j)
        a[i][j]=a[j][i]=1;
}
int dfs(int x,int contor)
{
    if(contor==0)
        viz[x]=1;
    for(int i=1; i<=n; i++)
    {
        if(viz[i]==0&&a[x][i]==1)
        {
            viz[i]=3-viz[x];
            return dfs(i,++contor);
        }
        if(viz[x]==viz[i]&&a[x][i]==1)
            return 0;
    }
    return 1;
}
int main()
{
    citire();
    cout<<dfs(1,0);
}