#include <iostream>
#include <cstdio>
#include <algorithm>
#include <cmath>
#include <cstdlib>
#include <ctime>
#include <utility>
#include <vector>

using namespace std;

typedef long double LD;
typedef pair<LD, LD> PLD;

int n, a, b;

LD GetRandom() {
    int x = rand() % 10000;
    int y = rand() % 10000;
    return (x * 10000 + y) / 10000000000.0;
}

vector<LD> GenSeq(int sz, int tgt) {
    vector<LD> t;
    t.push_back(GetRandom());
    while ((int) t.size() < sz) {
        t.push_back(t.back() + GetRandom());
    }
    if (sz < 2) return t;
    LD lo = 0, hi = 17.3 / (sz - 1);
    for (int i = 0; i < 100; ++i) {
        LD mid = (lo + hi) / 2.0;
        int num = 0;
        for (int y = 0; y < sz; ++y) {
            for (int x = 0; x < y; ++x) {
                if ((t[y] + y * mid) - (t[x] + x * mid) <= 10) ++num;
            }
        }
        if (num >= tgt) lo = mid;
        else hi = mid;
    }
    for (int i = 0; i < sz; ++i) t[i] += lo * i;
    return t;
}

int main() {
    srand(time(NULL));
    scanf("%d%d%d", &n, &a, &b);

    int u, v;
    for (u = 1; u <= n; ++u) {
        v = n - u;
        if (u >= v && u * (u - 1) / 2 + v * (v - 1) / 2 >= a) break;
    }

    int au = (int) (1.0 * a * u * (u - 1) / (u * (u - 1) + v * (v - 1)) + 0.5);
    int av = a - au;
    b -= u * (u - 1) / 2 + v * (v - 1) / 2;

    vector<LD> su = GenSeq(u, au);
    vector<LD> sv = GenSeq(v, av);

    vector<double> thresholds;
    for (auto s : su) {
        for (auto t : sv) {
            thresholds.push_back(sqrt(400 - (t - s) * (t - s)) - 0.000000001);
        }
    }
    sort(thresholds.begin(), thresholds.end());
    reverse(thresholds.begin(), thresholds.end());

    double c = thresholds[b - 1];  // U组的 y 坐标

    vector<PLD> pts;
    for (auto s : su) pts.push_back({ s, c });
    for (auto t : sv) pts.push_back({ t, 0 });

    for (auto [x, y] : pts) printf("%.12Lf %.12Lf\n", x, y);

    return 0;
}