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 = [...line]
        let result = null;
        arr.forEach(v=>{
            if(arr.indexOf(v) === arr.lastIndexOf(v) && !result){
                console.log(v)
                result = v
                return;
            }
        })
        !result && console.log(-1);
    }
}()