杨辉三角

杨辉三角

 

不带空格格式化的：

 

 

package com.baidu.zhidao;

public class Test {
	public static void main(String[] args) {
		final int Row = 6;
		int yh[][] = new int[Row][Row];
		for (int i = 0; i < Row; i++) {
			yh[i][0] = 1;
			yh[i][i] = 1;
		}
		for (int i = 2; i < Row; i++) {
			for (int j = 1; j < Row; j++) {
				yh[i][j] = yh[i - 1][j - 1] + yh[i - 1][j];
			}
		}
		for (int i = 0; i < Row; i++) {
			for (int j = 0; j <= i; j++) {
				System.out.print(yh[i][j] + " ");
			}
			System.out.println();
		}
	}
}

 

 

 

带空格格式化的

package com.baidu.zhidao;

import java.util.Scanner;

public class YangHuiTriangle {

	public static void main(String[] args) {
		long num = 0;
		while (true) {
			try {
				System.out.println("Please input a number!");
				Scanner s = new Scanner(System.in);
				num = s.nextInt();
				if (num < 2) {
					System.out.println("Please input the number of greater than 2!");
					break;
				}
				
				long middle =(num*2-1)/2;
				String[][] yh = new String[(int) num][(int) (num * 2 - 1)];
				
				for (int i = 0; i < num; i++) {
					for (int j = 0; j < num * 2 - 1; j++) {
						yh[i][j] = "0";
						yh[i][(int) (middle-i)] = "1";
						yh[i][(int) (middle+i)] = "1";
					}
				}

				for (int i = 2; i < num; i++) {
					for (int j = 1; j < num * 2 - 2; j++) {
						if(yh[i-1][j+1].equals("0")&&yh[i-1][j-1].equals("0")){
							
						}else{
							yh[i][j]=Integer.valueOf(yh[i-1][j-1])+Integer.valueOf(yh[i-1][j+1])+"";
						}						
					}
				}

				// print
				for (int i = 0; i < num; i++) {
					for (int j = 0; j < num * 2 - 1; j++) {
						if(yh[i][j].equals("0")){
							System.out.print(" ");
						}else{
							System.out.print(yh[i][j]);
						}
					}
					System.out.print("\n");
				}
			} catch (Exception e) {
				System.out.println("Please type in a number!");
			}
		}
	}

}