题解 | #密码截取#

就是求最长回文字符串

let str = readline();
let start = 0, end = 0;
let arr = str.split('');
let len = 0;
let result = '';
for(let i = 0; i < arr.length; i++) {
    let len1 = huiwen(i, i);
    let len2 = huiwen(i, i + 1);
    let temp = Math.max(len1, len2);
    if(temp > len) {
        len = temp;
//         start = i - Math.ceil(len/2) + 1;
//         end = i + Math.floor(len/2);
//         result = str.substr(start, len);
    }
}
function huiwen(i, j) {
    while(i >= 0 && j <= arr.length - 1 && arr[i] == arr[j]) {
        i--;
        j++;
    }
    return j - i - 1;
}
console.log(len);
// console.log(result);