E

#include <iostream>
#include <cmath>
#include <vector>
#include <queue>
#include <algorithm>
#include <string>
#include <stack>
#include <set>
#include <map>
#define pii pair <int,int>
using namespace std;
using ll = long long;
using ld = long double;
void cv(vector <int> &v){
    for (auto x: v) cout<<x<<' ';
    cout<<"\n";
}

void cvv(vector <vector <int> > &v){
    for (auto x: v) cv(x);
    cout<<"\n";
}
int n, mn, mx;
vector <vector <int> > G;
vector <pii> Edge;
void cG(){
    for (int i = 0; i < n;++i){
        cout<<"("<<i<<"): ";
        cv(G[i]);
    }
}

void cEdge(){
    cout<<Edge.size()<<"\n";
    for (auto x: Edge){
        cout<<x.first+1<<' '<<x.second+1<<"\n";
    }
}

bool cmp()

int main()
{
    /*ios::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);*/
    cin>>n>>mx>>mn;
    G.resize(n);
    for (int i = 0; i < n; ++i){
        if (G[i].size() == mn) continue;
        for (int j = 0; j < n && j != i; ++j){
            if (G[j].size() >= mn) continue;
            if (find(G[i].begin(), G[i].end(), j) == G[i].end() ){
                G[i].push_back(j);
                G[j].push_back(i);
                Edge.push_back({min(i, j), max(i, j)});
            }
            if (G[i].size() == mn){
                break;
            }
        }
    }
    //while ()
    cG();
    //cEdge();
}
/*
15 4 3

17 7 5
*/