function solution(id_list, report, k) { let members = {}; for (const r of report) { const [ reporter, reportee ] = r.split(" "); if (members[reportee]) { if (!members[reportee][1].includes(reporter)) { members[reportee][0]++; members[reportee][1].push(reporter); members[reportee][1] = [ ...new Set(members[reportee][1])]; } } else { members[reportee] = [1, [reporter]]; } } let answer = new Array(..