题解 | #查找重复元素#
查找重复元素
https://www.nowcoder.com/practice/871a468deecf453589ea261835d6b78b
function duplicates(arr) {
const list = []
const map = {}
arr.map(item=>{
if (map[item] == undefined) {
map[item] = 1
} else {
map[item] += 1
list.push(item)
}
})
return [...new Set(list)]
}
