【Java每日一题】— —第十七题：杨辉三角（等腰三角形）。

public class yanghui {
  public static void main(String[] args) {
 
    int[][] a = new int[10][10];
    for (int i = 0; i < 10; i++) {
      a[i][i] = 1;
      a[i][0] = 1;
    }
    for (int i = 2; i < 10; i++) {
      for (int j = 1; j < i; j++) {
        a[i][j] = a[i - 1][j - 1] + a[i - 1][j];
      }
    }
 
    for (int i = 0; i < 10; i++) {
      for (int k = 0; k < 2 * (10 - i) - 1; k++) {
        System.out.print(" ");
      }
      for (int j = 0; j <= i; j++) {
        // System.out.print(a[i][j] + "   ");
        System.out.printf("%3d ", a[i][j]);
      }
      System.out.println();
    }
  }
}