题解 | #自守数#

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

void (async function () {
    // Write your code here
    while ((line = await readline())) {
        const n = parseInt(line);
        let number = 0;
        for (let i = 0; i <= n; i++) {
            let pow = (i * i).toString();
            let m = pow.length;
            let strI = i.toString();
            let s = strI.length;
            for (let j = m - 1; j >= 0; j--) {
                if (s > 0) {
                    if (pow[j] == strI[s - 1]) {
                        --s;
                    } else break;
                }
                if (s === 0) {
                    number++;
                    break;
                }
            }
        }
        console.log(number);
    }
})();