#include <bits/stdc++.h>
#define rep(i, n) for (int i = 0; i < n; ++i)
typedef long long ll;
using namespace std;

int main() {
    cin.tie(0)->sync_with_stdio(0);

    int H, W;
    cin >> H >> W;
    vector<int> A(H * W);
    rep(i, H * W) cin >> A[i];
    sort(A.begin(), A.end());

    rep(i, H) {
        rep(j, W) {
            cout << A[i * W + j] << " ";
        }
        cout << "\n";
    }

    return 0;
}