#include <bits/stdc++.h>
int INF = 10000000;
using namespace std;
int main() {
  int n, k;
  cin >> n >> k;
  for (int i = 0; i < n; i++) {
    for (int j = 0; j < n; j++) {
      if (i == j) {
        cout << k - (n - 1) << " ";
        continue;
      }
      cout << 1 << " ";
    }
    cout << endl;
  }
  return 0;
}
