#include <bits/stdc++.h>
typedef long long int ll;
#define endl            '\n'
#define pb             push_back
#define mp              make_pair
#define pll             pair<ll,ll> 
#define fill(x, y)     memset(x, y, sizeof(x))
#define all(x)         (x).begin(), (x).end()
#define debug(x)       { cerr << #x << " = " << x << endl; }
#define IO	       { ios_base::sync_with_stdio(false); cin.tie(0); }
#define read(x)	       freopen(x, "r", stdin)
#define write(x)       freopen(x, "w", stdout)
#define N       1000000

using namespace std;


const double inf = 1e18;
const double pi = acos(-1);

vector<pll> getbamboo(ll n){
    vector<pll> v;
    for(ll i=1; i<n; i++){
        v.pb(mp(i,i+1));
    }
    return v;
}

void printv(ll n, vector<pll> v){
    cout<< n<< " "<< v.size()<< endl;
    for(ll i=0; i<v.size(); i++){
        cout<< v[i].first<< " "<< v[i].second<< endl;
    }
    return;
}

void solve() {
    string s;
    cin >> s;
    ll a = 0, b = 0 ,flag = 0; 
    for (int i=0; i<s.size(); i++) {
        if(s[i] == '/') {
            flag = 1;
        } else {
            if (flag) {
                b = (b*10) + (s[i] - '0');
            } else {
                a = (a * 10) + (s[i] - '0');
            }
        }
    }
    //cout << a << " " << b<< endl;
    //return;
    //cin>> a>> b;
    if(b<=2){
        if(b==1) a*=2;
        vector<pll> v = getbamboo(a+1);
        printv(a+1,v);
        return;
    }
    if(a<b){
        if(a+1<b){
            cout<< "impossible\n";
        }
        else{
            vector<pll> v;
            for(ll i=2; i<=b; i++){
                v.pb(mp(1,i));
            }
            printv(b,v);
        }
        return;
    }
    ll n = a/b + 1;
    ll k;
    while(true){
        n++;
        k = (n*(n-1)+2*(b*(n-1)-a)-1)/(2*(b*(n-1)-a));
        if(k*a<=N) break;
    }
    vector<pll> v = getbamboo(n);
    ll m = n+1;
    ll ka = n*(n-1)/2 , kb = n;
    //cout<< "---- "<< k<< " "<<ka<< " "<< kb<< endl;
    ll g = (k*a-ka)/(k*b-kb), h = (k*a-ka)%(k*b-kb);
    for(ll i=0; i<k*b-kb; i++){
        if(h){
            v.pb(mp(g+1,m));
            h--;
        }
        else{
            v.pb(mp(g,m));
        }
        m++;
    }
    printv(m-1,v);
}

int main() {
    IO;
    cout << fixed << setprecision(10);
    solve();
}