语法练习

#include <iostream>

using namespace std;
int n;

int main(int argc, char** argv) {
  while (cin >> n, n) {
    for (int y = 0; y < n; ++y) {
      for (int x = 0; x < n; ++x)
        cout << (1 << x + y) << ' ';
      cout << endl;
    }
    cout << endl;
  }

  return 0;
}