字符串中连续最多的字符&次数

　　双层for循环

const repeatStrAndNumsByDoubleLoop = (str = 'aabbbcccddeeefffff') => {
    const res = {
        char: '',
        len: 0
    }
    const { length } = str
    for(let i = 0; i < length; i++){
        let charLen = 1
        const curValue = str[i]
        for(let j = i + 1; j < length; j++){
            const nextValue = str[j]
            if(curValue === nextValue){
                charLen += 1
            }
            if(curValue !== nextValue || j === length - 1){
                if(charLen > res.len){
                    res.char = curValue
                    res.len = charLen
                }
                i = j - 1 // 进行跳步 减少时间复杂度
                break
            }
        }
    }
    return res
}

　　双指针　　

　　正则