题解 | #找出字符串中第一个只出现一次的字符#

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())) {
        let arr = new Map();
        for (let i of line) {
            if (arr.has(i)) arr.set(i, arr.get(i) + 1);
            else arr.set(i, 1);
        }
        let key = arr.keys();
        let final = "-1";
        while ((c = key.next().value)) {
            if (arr.get(c) === 1) {
                final=c;
                break;
            }
        }
        console.log(final);
    }
})();