#include <bits/stdc++.h>
using namespace std;
#define endl '\n'
const int N = 1e6 + 5;
#define int long long
typedef pair<int, int> PII;
#define MAX LONG_LONG_MAX
int ar[N], f[N];
void solve()
{
    int a, b;
    scanf("%lld/%lld", &a, &b);
    int num = 1;

    while (1)
    {
        int x = (1 + num * (b - 1)) * num * (b - 1) / 2;
        if(x==0)
            break;
        if (x < num * a)
            num++;
        else
            break;
    }
    a = a * num, b = b * num;
    if (b - 1 > a)
    {
        cout << "impossible" << endl;
        return;
    }
    num = b * (b - 1) / 2 - a;

    for (int i = 2; i <= b; i++)
        f[i] = i - 1;

    for (int i = b; i > 1; i--)
    {
        int x = i - 2;
        if (num >= x)
        {
            f[i] = 1;
            num -= x;
        }
        else if (num)
        {
            f[i] = i - num - 1;
            break;
        }
        if (num <= 0)
            break;
    }
    cout << b << " " << b - 1 << endl;
    for (int i = 2; i <= b; i++)
    {
        cout << f[i] << " " << i << endl;
    }
}
signed main()
{

    solve();
    return 0;
}