题解 | #最长回文子串#

const rl = require("readline").createInterface({ input: process.stdin });
var iter = rl[Symbol.asyncIterator]();
const readline = async () => (await iter.next()).value;

void async function () {
    const str = await readline();
    if(str.length == 1) return console.log(1)
    const dfs = (i,j) => {
        while(i>=0 && j<str.length && str[i]===str[j]) {
            i--;
            j++;
        }
        // console.log(i,j);
        return j-i-1;
    }
    let max = 0;
    for(let i = 0; i < str.length; i++){
        max = Math.max(max,dfs(i,i),dfs(i,i+1));
    }
    console.log(max);
}()