#include <bits/stdc++.h>

#define rep(i, n) for (int i = 0; i < (int)(n); ++i)
#define rep2(i, a, b) for (int i = (int)(a); i < (int)(b); ++i)
#define rrep(i, n) for (int i = (int)(n) - 1; i >= 0; --i)
#define rrep2(i, a, b) for (int i = (int)(b) - 1; i >= (int)(a); --i)

#define all(v) begin(v), end(v)

using namespace std;

using ll = long long;

constexpr ll inf = 1e18;

template<class T, class U> bool chmin(T& a, const U& b) { return a > b ? a = b, true : false; }
template<class T, class U> bool chmax(T& a, const U& b) { return a < b ? a = b, true : false; }

int main() {
    int N, S, T; cin >> N >> S >> T;
    vector<vector<int>> A(N, vector<int>(S));
    rep (i, N) rep (j, S) cin >> A[i][j], --A[i][j];
    vector<int> B(T);
    rep (i, N) rep (j, S) ++B[A[i][j]];
    rep (bt, 1 << N) {
        vector<int> cnt(T);
        rep (i, N) {
            if (bt >> i & 1) ++cnt[A[i][0]];
            else ++cnt[A[i][1]];
        }
        bool ok = true;
        rep (i, T) {
            if (abs(cnt[i] * 2 - B[i]) > 1) ok = false;
        }
        if (ok) {
            rep (i, N) {
                if (bt >> i & 1) cout << A[i][0] + 1 << " " << A[i][1] + 1 << endl;
                else cout << A[i][1] + 1 << " " << A[i][0] + 1 << endl;
            }
            return 0;
        }
    }
}