#include <bits/stdc++.h>
using namespace std;
#define int long long
pair<int,int> parse(string s){
	for(int i = 0; i<s.size(); i++){
		if(s[i]=='/'){
			int a = stoll(s.substr(0,i));
			int b = stoll(s.substr(i+1));
			return make_pair(a,b);
		}
	}
	return {0,0};
}
signed main(){
	cin.tie(nullptr)->sync_with_stdio(false);
	/*
	anything < 1 that's not n-1/n is not possible
	n-1/n is possible
	1/1 is possible

	
	*/
	string s;
	cin >> s;
	auto [a,b] = parse(s);
	if(a<b-1){
		cout << "impossible\n";
		return 0;
	}
	if(a<b){
		cout << b << ' ' << b-1 << '\n';
		for(int i = 1; i<b; i++){
			cout << i << ' ' << b << '\n';
		}
		return 0;
	}
	a*=100000/b; b*=100000/b;
	vector<int>ans(b+1,b);
	int dif = a-(b-1);
	int cur = 1;
	int r = b-1;
	while(dif>0){
		int v = 1;
		for(int i = 1; i<=100000; i++){
			if(i*(i+1)/2<=dif){
				v = i;
			}
			else{
				break;
			}
		}
		dif-=v*(v+1)/2;
		ans[cur] = r;
		for(int i = 1; i<v; i++){
			ans[cur+i] = cur+i-1;
		}
		r--;
		cur+=v;
		cout << v << '\n';
	}
	vector<vector<int>>adj(b+1);
	cout << b << ' ' << b-1 << '\n';
	for(int i = 1; i<b; i++){
		int x = i+1;
		int y = ans[i]%b+1;
		adj[x].push_back(y);
		adj[y].push_back(x);
		cout << i+1 << ' ' << ans[i]%b+1 << '\n';
	}
	//cout << sum << '\n';
	return 0;
}