#include <bits/stdc++.h>
#define ll long long
#define pb push_back

using namespace std;

int main()
{
    ll a, b;
    cin >> a;
    getchar();
    cin >> b;

    ios_base::sync_with_stdio(false);
	cin.tie(nullptr);
	cout.tie(nullptr);

    if(a<=b)
    {
        if(a==b) cout << "3 2\n1 2\n2 3";
        else if(a+1==b)
        {
            cout << b << " " << a << '\n';
            for(int i=1; i<=a; i++) cout << 1 << " " << i + 1 << "\n";
        }
        else cout << "impossible";
    }
    else
    {
        ll cnt = 1, n = 2*a-2*b, x = 1;
        while((x*n-1)*b-2*a<0) x++;
        vector<int> ans;

        n = 2*(a-b)*x-1;
        for(int i=1; i<=n; i++)
        {
            ans.pb(i);
            cnt++;
        }

        for(int i=1; i<=x*(b*n-2*a); i++)
        {
            ans.pb(1);
            cnt++;
        }

        cout << cnt << " " << cnt - 1 << "\n";
        for(int i=1; i<=cnt-1; i++)
        {
            cout << ans[i-1] << " " << i + 1 << "\n";
        }
    }
}