题解 | #提取不重复的整数#

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

void async function () {
  
    const num = await readline()
    const arr = []
    for(let i=num.length;i >= 0; i--){
        if(!arr.includes(num[i])){
            arr.push(num[i])
        }
    }
    console.log(arr.join(''))
}()