找出字符串中连续出现最多的字符和个数

function getMaxCharacters(str) {
        const map = {}
        var arr = str.match(/(\w)\1+/g)
        var max = arr[0].length
        arr.map(v => max = Math.max(max, v.length))
        const maxArr = arr.filter(v => v.length === max)
        maxArr.forEach(v => {
            map[v[0]] = v.length
        })
        return map
    }

    getMaxCharacters('abcaakjbb')  // { a: 2, b: 2 }

    console.log(getMaxCharacters('abcaakjbb'))