#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace __gnu_pbds;
template <class T>
using treap = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
#define int long long
#define REP(i, n) for (long long i = 0, max_i = (n); i < max_i; i++)
#define REPI(i, a, b) for (long long i = (a), max_i = (b); i < max_i; i++)
#define ALL(obj) begin(obj), end(obj)
#define RALL(obj) rbegin(obj), rend(obj)
#define fi first
#define se second
using ii = pair<int, int>;
vector<ii> dirs = {
    {1, 0}, {0, 1},  {-1, 0},  {0, -1},  // 4方向
    {1, 1}, {-1, 1}, {-1, -1}, {1, -1},  // 斜め
    {0, 0},                              // 自身
};
template <class T>
inline bool chmax(T &a, const T &b) {
    if (a < b) {
        a = b;
        return true;
    }
    return false;
}
template <class T>
inline bool chmin(T &a, const T &b) {
    if (a > b) {
        a = b;
        return true;
    }
    return false;
}
template <class T, class S>
vector<T> make_vec(size_t n, S x) {
    return vector<T>(n, x);
}
template <class T, class... Ts>
auto make_vec(size_t n, Ts... ts) {
    return vector<decltype(make_vec<T>(ts...))>(n, make_vec<T>(ts...));
}

// debug
template <class T>
ostream &operator<<(ostream &s, vector<T> &d) {
    REP(i, d.size()) s << d[i] << (i == d.size() - 1 ? "" : " ");
    return s;
}
template <class T>
ostream &operator<<(ostream &s, vector<vector<T>> &d) {
    REP(i, d.size()) s << d[i] << (i == d.size() - 1 ? "" : "\n");
    return s;
}
template <class T, class S>
ostream &operator<<(ostream &s, pair<T, S> &p) {
    s << "{" << p.first << ", " << p.second << "}";
    return s;
}
template <class T, class S>
ostream &operator<<(ostream &s, map<T, S> m) {
    for (auto it = m.begin(); it != m.end(); it++) {
        s << *it << (next(it) == m.end() ? "" : "\n");
    }
    return s;
}
template <class T, class S>
ostream &operator<<(ostream &s, unordered_map<T, S> m) {
    for (auto it = m.begin(); it != m.end(); it++) {
        s << *it << (next(it) == m.end() ? "" : "\n");
    }
    return s;
}
#ifdef _MY_DEBUG
#define dump(...)                                                                                                     \
    cerr << "/* " << #__VA_ARGS__ << " :[" << __LINE__ << ":" << __FUNCTION__ << "]" << endl, dump_func(__VA_ARGS__), \
        cerr << "*/\n\n";
#else
#define dump(...)
#define endl "\n"
#endif
void dump_func() { cerr << endl; }
template <class Head, class... Tail>
void dump_func(Head &&h, Tail &&... t) {
    cerr << h << (sizeof...(Tail) == 0 ? "" : ", "), dump_func(forward<Tail>(t)...);
}

struct Fast {
    Fast() {
        cin.tie(0);
        ios::sync_with_stdio(false);
    }
} fast;
mt19937 rnd(chrono::steady_clock::now().time_since_epoch().count());
constexpr int MOD = 1000000007;
// *************** TEMPLATE END ***************

struct HopcroftKarp {
    vector<vector<int>> graph;
    vector<int> dist, match;
    vector<bool> used, vv;

    HopcroftKarp(int n, int m) : graph(n), match(m, -1), used(n) {}

    void add_edge(int u, int v) { graph[u].push_back(v); }

    void bfs() {
        dist.assign(graph.size(), -1);
        queue<int> que;
        for (int i = 0; i < graph.size(); i++) {
            if (!used[i]) {
                que.emplace(i);
                dist[i] = 0;
            }
        }

        while (!que.empty()) {
            int a = que.front();
            que.pop();
            for (auto &b : graph[a]) {
                int c = match[b];
                if (c >= 0 && dist[c] == -1) {
                    dist[c] = dist[a] + 1;
                    que.emplace(c);
                }
            }
        }
    }

    bool dfs(int a) {
        vv[a] = true;
        for (auto &b : graph[a]) {
            int c = match[b];
            if (c < 0 || (!vv[c] && dist[c] == dist[a] + 1 && dfs(c))) {
                match[b] = a;
                used[a] = true;
                return (true);
            }
        }
        return (false);
    }

    int bipartite_matching() {
        int ret = 0;
        while (true) {
            bfs();
            vv.assign(graph.size(), false);
            int flow = 0;
            for (int i = 0; i < graph.size(); i++) {
                if (!used[i] && dfs(i)) ++flow;
            }
            if (flow == 0) return (ret);
            ret += flow;
        }
    }

    void output() {
        for (int i = 0; i < match.size(); i++) {
            if (~match[i]) {
                cout << match[i] << "-" << i << endl;
            }
        }
    }
};
signed main() {
    int n, m;
    cin >> n >> m;
    vector<set<int>> ss(n);
    REP(i, n) {
        REP(j, m) {
            int x;
            cin >> x;
            x--;
            ss[i].insert(x);
        }
    }
    auto b = make_vec<int>(n, m, 0);
    REP(j, m) {
        HopcroftKarp g(n, n);
        REP (i, n) {
            for (int x : ss[i]) {
                g.add_edge(x / m, i);
            }
        }
        int hoge = g.bipartite_matching();
        REP (i, n) {
            for (int x : ss[i]) {
                if (x / m == g.match[i]) {
                    ss[i].erase(x);
                    b[i][j] = x;
                    break;
                }
            }
        }
    }
    auto c = make_vec<int>(n, m, 0);
    {
        auto d = make_vec<int>(m, n, 0);
        REP (i, n) {
            REP (j, m) {
                d[j][i] = b[i][j];
            }
        }
        REP (j, m) sort(ALL(d[j]));
        REP (i, n) {
            REP (j, m) {
                c[i][j] = d[j][i];
            }
        }
    }
    REP (i, n) {
        REP (j, m) cout << b[i][j] + 1 << " ";
        cout << endl;
    }
    REP (i, n) {
        REP (j, m) cout << c[i][j] + 1 << " ";
        cout << endl;
    }
}


Measured memory_bytes: 1024