题目：

题解：

func deserialize(s string) *NestedInteger {
    index := 0
    var dfs func() *NestedInteger
    dfs = func() *NestedInteger {
        ni := &NestedInteger{}
        if s[index] == '[' {
            index++
            for s[index] != ']' {
                ni.Add(*dfs())
                if s[index] == ',' {
                    index++
                }
            }
            index++
            return ni
        }

        negative := s[index] == '-'
        if negative {
            index++
        }
        num := 0
        for ; index < len(s) && unicode.IsDigit(rune(s[index])); index++ {
            num = num*10 + int(s[index]-'0')
        }
        if negative {
            num = -num
        }
        ni.SetInteger(num)
        return ni
    }
    return dfs()
}