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import java.util.Scanner;
public class Main {
    static int[] mat = new int[31];
    public static void main(String args[]) {
        Scanner sc = new Scanner(System.in);
        mat[0] = 1;// 初始化第一个元素,也就是第一列的值全为1;
        int n = 0;
        while (sc.hasNext()) {
            n = sc.nextInt();
            triangle(n);
        }
    }
    public static void triangle(int n) {
        System.out.println(mat[0]);
        mat[n - 1] = 1;// 从后面往前面
        for (int i = 1; i < n; i++) {// 控制行数
            mat[i] = 1;
            for (int j = i - 1; j > 0; j--) {
                mat[j] = mat[j] + mat[j - 1];
                if (mat[j] < 0) {
                    return;
                }
            }
            for (int j = 0; j <= i; j++) {
                if (j == 0) {
                    System.out.print(mat[j]);
                } else {
                    System.out.print(" " + mat[j]);
                }
            }
            System.out.println();
        }
        System.out.println();
    }
}
原文:http://blog.csdn.net/hncu1306602liuqiang/article/details/46408971