关于数组去重

// 关于数组去重

const list = [3, 3, 4, 5, 2, 3, 34, 45, 38, 19, 34, 90, 3, 3, 6, 7, 8,]

// 使用filter
function run (list) {
    const list2 = []
    list.filter(item => {
        if (!list2.includes(item)) {
            list2.push(item)
        }
    })
    return list2
}

console.log(run(list))

// 使用map
function run2 (list) {
    const map = new Map()
    list.map((item, index) => {
        map.set(item, index)
    })
    const list2 = []
    map.forEach((value, key) => {
        list2.push(key)
        // console.log(key)
    })
    return list2
}

console.log(run2(list))