1027.欧拉回路

#include<iostream>
#include<cstring>
using namespace std;

int main(){
    int degree[1001];
    int n,m,i,a,b;
    while(cin>>n){
        if(n==0) break;
        cin>>m;
        memset(degree,0,sizeof(degree));
        for(i=0;i<m;i++){
            cin>>a>>b;
            degree[a]++;
            degree[b]++;
        }
        bool flag=true;
        for(i=1;i<=n;i++){
            if(degree[i]%2==1) flag=false;
        }
        if(flag) cout<<"1"<<endl;
        else cout<<"0"<<endl;
    }
    return 0;
}