#include <bits/stdc++.h>
using namespace std;

#define rep(i, a, b) for (auto i = a; i < (b); ++i)
#define repr(i, a, b) for (auto i = (a) - 1; i >= (b); --i)
#define pb push_back
#define eb emplace_back
#define all(x) begin(x), end(x)
#define sz(x) int((x).size())

using ll = long long;
using pii = pair<int, int>;
using vi = vector<int>;
using vll = vector<ll>;
using vii = vector<pii>;

template<class T>
inline bool cmax(T &a, const T &b) {
    return a < b ? a = b, 1 : 0;
}

template<class T>
inline bool cmin(T &a, const T &b) {
    return b < a ? a = b, 1 : 0;
}

const int inf = 0x3f3f3f3f;
const ll linf = 1e18;
const double dinf = numeric_limits<double>::infinity();

using ld = long double;

int main() {
    cin.tie(0)->sync_with_stdio(0);
    cin.exceptions(cin.failbit);
    
    int n, m;
    cin >> n >> m;
    ld l;
    cin >> l;

    auto len = [&](vector< pair<ld, ld> > p) {
        sort(all(p), [&](const auto &a, const auto &b) {
            return a.second < b.second;
        });
        ld ans = 0;
        rep(i, 1, sz(p)) {
            ans += hypotl(p[i].first - p[i - 1].first, p[i].second - p[i - 1].second);
        }
        return ans;
    };

    vector< pair<ld, ld> > p = {{0, 0}, {n, m}};
    ld L = hypotl(n, m);
    vector< pair<ld, ld> > q;
    if (m % 2 == 1) {
        rep(i, 1, m) {
            if (i % 2 == 1) {
                q.eb(n, i);
            } else {
                q.eb(0, i);
            }
        }
    } else {
        rep(i, 1, m - 1) {
            if (i % 2 == 1) {
                q.eb(n, i);
            } else {
                q.eb(0, i);
            }
        }
        q.eb(n, m - 2 + 2.l / 3);
        q.eb(0, m - 2 + 4.l / 3);
    }

    ld lx = 0, ly = 0;
    for (auto &[y, x] : q) {
        auto tmp = p;
        tmp.eb(y, x);
        // cerr << len(tmp) << endl;
        if (len(tmp) < l - 1e-9) {
            p.eb(y, x);
            lx = x;
            ly = y;
            continue;
        }

        ld ty = ly + (x - lx) / (m - lx) * (n - ly);
        ld lo = y, hi = ty;
        int invert = 0;
        if (lo > hi) {
            invert = 1;
            swap(lo, hi);
        }

        while (hi - lo > 1e-9) {
            ld mid = (lo + hi) / 2;
            tmp = p;
            tmp.eb(mid, x);
            // cerr << mid << ' ' << len(tmp) << endl;
            if (len(tmp) > l) {
                if (invert) {
                    hi = mid;
                } else {
                    lo = mid;
                }
            } else {
                if (invert) {
                    lo = mid;
                } else {
                    hi = mid;
                }
            }
        }
        p.eb(lo, x);
        break;
        // ld ty = ly + (m - lx) * (m - ly);
    }

    sort(all(p), [&](const auto &a, const auto &b) {
        return a.second < b.second;
    });

    cout << sz(p) << '\n';
    cout << fixed << setprecision(15);
    for (auto &[x, y] : p) {
        cout << x << ' ' << y << '\n';
    }

    // cerr << len(p) << endl;

    return 0;
}