LeetCode 實作解說系列-Palindrome Number

題目解說

原題目

Given an integer x, return true if x is palindrome integer.

An integer is a palindrome when it reads the same backward as forward.

For example, 121 is a palindrome while 123 is not.

Example 1:

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Input: x = 121
Output: true
Explanation: 121 reads as 121 from left to right and from right to left

Example 2:

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Input: x = -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:

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Input: x = 10
Output: false
Explanation: Reads 01 from right to left. Therefore it is not a palindrome.

Constraints:

-231 <= x <= 231 - 1

翻譯

給定一個整數x，回傳x是不是個相反數。舉例來說121相反為121，回傳true，-121相反為121-，回傳false。

解題策略

將x轉為字串xstr，再將xstr利用reverse函數做字序的反轉，最後將x與xstr做一般相等比較。

JS程式碼

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var isPalindrome = function(x) {
    let xstr = x.toString().split("").reverse().join("")
    console.log(xstr)
    if(x==xstr){
        return true;
    }
    else{
        return false;
    }
};