程序员子悠 · 好记性不如烂笔头

Introduction

• Algorithm - Learning Algorithm
• Review - Learning English
• Tip - Learning Techniques
• Share - Learning Influence

Let's do it!!!

Algorithm

ReverseInteger

1. Description

Given a 32-bit signed integer, reverse digits of an integer.
Example 1:
Input: 123
Output: 321
Example 2:
Input: -123
Output: -321
Example 3:
Input: 120
Output: 21

2. My Solution

package com.silence.arts.leetcode.first;

/**
 * <br>
 * <b>Function：</b><br>
 * <b>Author：</b>@author Silence<br>
 * <b>Date：</b>2018-07-18 23:52<br>
 * <b>Desc：</b>无<br>
 */
public class ReverseInteger_7 {

    /**
     * 判断数字是否是负数，负数则截取第一位符号位
     * @param x
     * @return
     */
    public static int reverse(int x) {
        int resultNext;
        try {
            if (x < 0) {
                String string = String.valueOf(x);
                String prev = string.substring(0, 1);
                StringBuilder next = new StringBuilder(string.substring(1));
                resultNext = Integer.parseInt(prev + Integer.parseInt(next.reverse().toString()));
            }else {
                StringBuilder string = new StringBuilder(String.valueOf(x));
                resultNext = Integer.parseInt(string.reverse().toString());
            }
        }catch (Exception e) {
            resultNext = 0;
        }
        return resultNext;
    }

    public static void main(String[] args) {
        System.out.println(reverse(1534236469));
    }
}

Thinking

1. Transfer int to String
2. Reverse the String and Splice minus sign if it has

思路

1. 将整型转换为字符串
2. 反转字符串并且组装符号位（如果为负数的话）

PalindromeNumber

1. Description

Determine whether an integer is a palindrome. An integer is a palindrome when it reads the same backward as forward.
Example 1:
Input: 121
Output: true
Example 2:
Input: -121
Output: false
Explanation: From left to right, it reads -121. From right to left, it becomes 121-. Therefore it is not a palindrome.
Example 3:
Input: 10
Output: false
Explanation: Reads 01 from right to left. Therefore it is not a palindrome.

2. My Solution

package com.silence.arts.leetcode.first;

/**
 * <br>
 * <b>Function：</b><br>
 * <b>Author：</b>@author Silence<br>
 * <b>Date：</b>2018-07-31 23:38<br>
 * <b>Desc：</b>无<br>
 */
public class PalindromeNumber_9 {

    /**
     * 转换为字符串，然后反转进行比较
     * 注意before.reverse() 会将before改变，不会生成新的内存对象
     *
     * @param x
     * @return
     */
    public static boolean isPalindrome(int x) {
        String b = String.valueOf(x);
        StringBuilder before = new StringBuilder(b);
        String after = before.reverse().toString();
        return b.equals(after);
    }


    public static void main(String[] args) {
        System.out.println(isPalindrome(-121));
    }
}

Thinking

1. Transfer int to String;
2. Reverse the String and then compare it with original String.

思路

1. 将数字转换成字符串
2. 反转字符串与反转前的字符串进行比较

Review

10 Common Software Architectural Patterns in a nutshell

This author explains 10 different kinds of Architectural Patterns briefly. Here are they.

1. Layered pattern
2. Client-server pattern
3. Master-slave pattern
4. Pipe-filter pattern
5. Broker pattern
6. Peer-to-peer pattern
7. Event-bus pattern
8. Model-view-controller pattern
9. Blackboard pattern
10. Interpreter pattern
    

Tips

1. jQuery prop()

//this code is not working you should use below code.
//$('#abc').attr('checked', true);
//It's working!
$('#abc').prop('checked', true);

2. GITHUBER - 开发者的新标签页

• This is an extension of Chrome that will help you to find the good project on Github weekly. Something like this.
  

3. Process On

• This is a very good Free online drawing website. It also can be a real-time collaboration website. You can use it for yourself also you can use it with your friends together.
  

Share

Sharing

Last week was a busy week. I didn't do anything extra but work. Nothing else to share.

One more thing

• Personal Medium Home Page: https://medium.com/@zhuxiang134
• Personal Website: https://zxsilence.cn/