#include <bits/stdc++.h>

using namespace std;
const int INF = 0x3f3f3f3f;

// 扩展知识：欧拉通路，欧拉回路
// https://www.cnblogs.com/graytido/p/10421927.html
// 并查集+欧拉回路
typedef long long LL;
const LL N = 1e3 + 7;
const LL MOD = 1e9 + 7;
int pre[N];
int n, m;
int degree[N];

int find(int x) //查找根结点
{
    int r = x;
    while (r != pre[r]) //寻找根结点
        r = pre[r];
    int i = x, j;
    while (pre[i] != r) //路径压缩
    {
        j = pre[i];
        pre[i] = r;
        i = j;
    }
    return r;
}

int main() {
    ios::sync_with_stdio(false);
    while (cin >> n && n) {
        cin >> m;
        memset(degree, 0, sizeof(degree));
        for (int i = 1; i <= n; i++)
            pre[i] = i;
        while (m--) {
            int a, b;
            cin >> a >> b;
            int fa = find(a);
            int fb = find(b);
            if (fa != fb) {
                pre[a] = b;
                degree[a]++;
                degree[b]++;
            }
        }
        int flag = 1;
        for (int i = 2; i <= n; i++) {
            if (degree[i] & 1 || pre[i] != pre[1]) {
                flag = 0;
                break;
            }
        }
        cout << flag << endl;
    }
    return 0;
}