典型案例：arr1 [ 1, 2, 5, 2, 1, 8, 9, 5, 2, 8, 9, 10] 按照 arr2 [1, 5, 9, 8, 2, 10]的顺序排序
结果: [1,1,5,5,9,9,8,8,2,2,2,10]
思路:
function solution(arr1, arr2) {
const map = new Map(),
len1 = arr1.length,
len2 = arr2.length,
res = []
for (let i = 0; i < len2; i += 1) {
map.set(arr2[i], [])
}
for (let i = 0; i < len1; i += 1) {
const item = arr1[i]
if (map.has(item)) {
const temp = map.get(item)
temp.push(item)
}
}
map.forEach((value) => {
res = res.concat(value)
})
return res
}