#include <fstream>

using namespace std;
ifstream fin ("flori.in");
ofstream fout ("flori.out");
int n, m, a[1005][1005], Next[1005], Size[1005], v[1005];
bool freq[1005];
void init(int n) {
    for(int i = 1; i <= n; i++) {
        v[i] = i;
        Size[i] = 1;
        Next[i] = i;
    }
}
int Find(int x) {
    return v[x];
}
void unit(int x, int y) {
    int fx = Find(x);
    if(fx != Find(y)) {
        Size[x] += Size[y];
        int i = y;
        do {
            v[i] = fx;
            i = Next[i];
        }
        while(i != y);
        int nx = Next[x];
        Next[x] = Next[y];
        Next[y] = nx;
    }
}
int main()
{
    fin >> n >> m;
    init(n);
    for(int i = 1; i <= n; ++i)
        for(int j = 1; j <= m; ++j)
            fin >> a[i][j];
    for(int x = 1; x < n; ++x) {
        for(int j = 1; j <= m; j++) freq[a[x][j]] = 1;
        for(int i = x + 1; i <= n; ++i)
            for(int j = 1; j <= m; ++j)
                if(freq[a[i][j]]) {
                        unit(x, i);
                        break;
                }
        for(int j = 1; j <= 1000; ++j) freq[j] = 0;
    }
    for(int i = 1; i <= n; ++i) {
        int cnt = 0;
        for(int j = 1; j <= n; ++j)
            if(v[j] == i) fout << j << " ", ++cnt;
        if(cnt) fout << "\n";
    }
    return 0;
}