https://programmers.co.kr/learn/courses/30/lessons/92334?language=javascript
function solution(id_list, report, k) {
let reports = [...new Set(report)].map(a=>{return a.split(' ')});
let counts = new Map();
for (const bad of reports){
counts.set(bad[1],counts.get(bad[1])+1||1)
}
let good = new Map();
for(const report of reports){
if(counts.get(report[1])>=k){
good.set(report[0],good.get(report[0])+1||1)
}
}
let answer = id_list.map(a=>good.get(a)||0)
return answer;
}