Cho mảng các mảng con [name, email1, email2...]. Gộp các mảng con có chung email (union-find). Kết quả: mỗi nhóm [name, emails...] với emails sắp xếp.
Ví dụ
const arr = [ ["John", "johnsmith@mail.com", "john00@mail.com"], ["John", "johnnybravo@mail.com"], ["John", "johnsmith@mail.com", "john_newyork@mail.com"], ["Mary", "mary@mail.com"] ]; const recusiveMatch = (included, i, tmp, arr, res) => { for(let j = 1; j < arr[i].length; j += 1) { let currentEmail = arr[i][j]; if(included.has(currentEmail)) continue; res.push(currentEmail); included.add(currentEmail); let currentAccountIndexes = tmp.get(currentEmail); for(let c = 0; c < currentAccountIndexes.length; c += 1) { let currentIndex = currentAccountIndexes[c]; if(i !== currentIndex) { recusiveMatch(included, currentIndex, tmp, arr, res); } } } }; const merge = (arr) => { const tmp = new Map(), included = new Set(), res = []; arr.forEach((account, i) => { for(let u = 1; u < account.length; u += 1) { let currentEMail = account[u]; tmp.set(currentEMail, tmp.get(currentEMail) || []); tmp.get(currentEMail).push(i); } }); arr.forEach((account, i) => { if(!included.has(arr[1])) { let u = []; recusiveMatch(included, i, tmp, arr, u); if(u.length) { res.push(u); u.sort(); u.unshift(account[0]); } } }); return res; }; console.log(merge(arr));
Kết quả
[ [ 'John', 'john00@mail.com', 'john_newyork@mail.com', 'johnsmith@mail.com' ], [ 'John', 'johnnybravo@mail.com' ], [ 'Mary', 'mary@mail.com' ] ]