将一个指定数组去重并给出数组中出现最多的数的值

不足之处,还望指出,邮箱winnerwly@qq.com

方法-

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const arr = [1, 2, 2, 2, 2, 2, 2, 2, 3, 3, 4, 4, 4, 5, 5, 5, 5]

var tmpObj = {}

arr.forEach((item) => {
    if (tmpObj[item]) {
        tmpObj[item].count++
    } else {
        tmpObj = {
            ...tmpObj,
            [item]: {
                count: 1
            }
        }
    }

})
var tmpArr = []
for (var key in tmpObj) {
    tmpArr.push({ val: key, count: tmpObj[key].count })
}

const maxVal = tmpArr.sort((a, b) => a.count < b.count).slice(0, 1)[0].val

console.log('maxVal', maxVal)
// 最多的数的值

const newArr = Array.from(new Set(arr))
// 数组去重

方法二

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const arr = [1, 2, 2, 2, 2, 2, 2, 2, 3, 3, 4, 4, 4, 5, 5, 5, 5]

const newArr = Array.from(new Set(arr))
// 数组去重

const tmpArr = newArr.map((i) => {
    let item = {
        val: i,
        count: 0
    }
    arr.map((j) => {
        if (j === i && arr.includes(i)) {
            item.count++
        }
    })
    return item
})

const maxVal = tmpArr.sort((a, b) => a.count < b.count).slice(0, 1)[0].val

console.log('maxVal', maxVal)
// 最多的数的值

方法三(最简洁得一种方法)

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const arr = [7, 2, 2, 2, 2, 2, 2, 2, 3, 3, 4, 4, 4, 5, 5, 5, 5]

const newArr = [...new Set(arr)]

const maxVal = newArr.map((item) => ({ val: item, count: arr.reduce((a, v) => v === item ? a + 1 : a + 0, 0) })).sort((a, b) => a.count < b.count).slice(0, 1)[0].val

console.log('maxVal', maxVal)

方法很粗糙,欢迎指教