java 实现杨辉三角

import java.util.Scanner;

public class YanghuiTriangle {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        System.out.print("请输入要打印的行数：");
        int n = sc.nextInt();
        int[][] arr = new int[n][n];
        for (int i = 0; i < n; i++) {
            for (int j = 0; j <= i; j++) {
                if (j == 0 || i == j) {
                    arr[i][j] = 1;
                } else {
                    arr[i][j] = arr[i - 1][j - 1] + arr[i - 1][j];
                }
                System.out.print(arr[i][j] + " ");
            }
            System.out.println();
        }
    }
}

运行结果：

请输入要打印的行数：6
1
1 1
1 2 1
1 3 3 1
1 4 6 4 1
1 5 10 10 5 1