#include <bits/stdc++.h>
using namespace std;
int main() {
  int n;
  cin >> n;
  for (int i = 0; i < n; i++) {
    for (int j = 0; j < n; j++) {
      if (j % 2 == 0) {
        cout << (i) + (j * n) + 1 << " ";
      } else {
        cout << (n - i) + (j * n) << " ";
      }
    }
    cout << endl;
  }
}
