#include <bits/stdc++.h>
using namespace std;
int random(int n){
	return (long long)rand()*rand()%n;
}
int main()
{
	freopen("data.in","w",stdout);
	srand((unsigned)time(0));
	int n,m;
	//注：n为节点数，m为边数，不存在重边，自环，且为连通图，保证数据范围为：5<=n<=m<=n(n-1)/4<=10**6 
	cin>>n>>m;
	pair<int,int> e[1000005];
	map<pair<int,int>,bool> h;
	for(int i = 1;i<n;i++){
		int fa = random(i)+1;
		e[i] = make_pair(fa,i+1);
		h[e[i]] = h[make_pair(i+1,fa)] = 1;
	} 
	for(int i = n;i<=m;i++){
		int x,y;
		do{
			x = random(n)+1,y = random(n)+1;
		}while(x==y||h[make_pair(x,y)]);
		e[i] = make_pair(x,y);
		h[e[i]] = h[make_pair(y,x)] = 1;
	}
	random_shuffle(e+1,e+m+1);
	for(int i = 1;i<=m;i++){
		cout<<e[i].first<<e[i].second<<endl;
	}
	return 0;
}