【算法】程序猿不写代码是不对的74

package com.kingdz.algorithm.time201706;

import java.util.Arrays;

/**
* <pre>
* 步骤问题
*
* 题目说明见上一个算法
* 这次我们会输出每个数字的来源是谁
* 第一个是元素位置，第二个是来源，第三个是次数
* </pre>
*
* @author kingdz
*
*/
public class Algo23 {

public static void main(String[] args) {
int n = 50;
String[] arr = new String[n + 1];
arr[0] = "0,0,0";
for (int i = 0; i < arr.length; i++) {
int now = Integer.parseInt(arr[i].split(",")[2]) + 1;
int a = i * 2;
int b = i + 1;

if (a < arr.length && arr[a] == null) {
arr[a] = a + "," + i + "," + now;
}

if (b < arr.length && arr[b] == null) {
arr[b] = b + "," + i + "," + now;
}

if (a == n || b == n) {
break;
}
}

System.out.println(Arrays.toString(arr));
}

}