const _isPalindrome = string => { // 补全代码 let strArr = string.split(','); let len = strArr.length; if(len%2!==0){ let mid = Math.floor(len/2); let l = r = mid; while(l>0){ if(strArr[l] !== strArr[r]){ return false; }else{ l--; r++; continue; } } return true; } }
for (let i = 0; i <= Math.floor(string.length/2); i++) { if(string[i]==string[string.length-i-1]){ if(i==Math.floor(string.length/2)){ return true } }else{ return false } }
<script type="text/javascript"> const _isPalindrome = string => { // 补全代码 let resever = string.split('').reverse() return resever.join('') == string ? true : false } </script>
<!DOCTYPE html> <html> <head> <meta charset=utf-8> </head> <body> <script type="text/javascript"> const _isPalindrome = string => { // 补全代码 let length = string.length; for(let i=0;i<Math.floor(length/2);i++){ if(string[i]!=string[length-1-i]) return false; } return true; } </script> </body> </html>
<script type="text/javascript"> const _isPalindrome = string => { // 补全代码 //建立正序列表 let oldArr = string.split('').join(); //建立一个逆序列表(将数组进行反转) let newArr = string.split('').reverse().join(); //将两个列表使用join转化为字符串 //进行判断两者是否相等 if (oldArr == newArr) { return true; } return false; } </script>
const _isPalindrome = string => { // 补全代码 return string.split('').reverse().join('') == string }
const _isPalindrome = s => { let m = s.length; let res = []; let dp = new Array(m).fill([]).map(() => new Array(m).fill(false)); // 遍历的顺序,从下到上,从左到右 for (let i = m - 1; i >= 0; i--) { for (let j = i; j < m; j++) { if (s[i] === s[j]) { if (j - i <= 2 || dp[i + 1][j - 1]) { dp[i][j] = true; } } } } return dp[0][s.length - 1]; }