Solution.go

/**
 * // This is the interface that allows for creating nested lists.
 * // You should not implement it, or speculate about its implementation
 * type NestedInteger struct {
 * }
 *
 * // Return true if this NestedInteger holds a single integer, rather than a nested list.
 * func (n NestedInteger) IsInteger() bool {}
 *
 * // Return the single integer that this NestedInteger holds, if it holds a single integer
 * // The result is undefined if this NestedInteger holds a nested list
 * // So before calling this method, you should have a check
 * func (n NestedInteger) GetInteger() int {}
 *
 * // Set this NestedInteger to hold a single integer.
 * func (n *NestedInteger) SetInteger(value int) {}
 *
 * // Set this NestedInteger to hold a nested list and adds a nested integer to it.
 * func (n *NestedInteger) Add(elem NestedInteger) {}
 *
 * // Return the nested list that this NestedInteger holds, if it holds a nested list
 * // The list length is zero if this NestedInteger holds a single integer
 * // You can access NestedInteger's List element directly if you want to modify it
 * func (n NestedInteger) GetList() []*NestedInteger {}
 */
func deserialize(s string) *NestedInteger {
	if s[0] != '[' {
		v, _ := strconv.Atoi(s)
		ans := NestedInteger{}
		ans.SetInteger(v)
		return &ans
	}
	stk := []*NestedInteger{}
	x := 0
	neg := false
	for i, c := range s {
		if c == '-' {
			neg = true
		} else if c >= '0' && c <= '9' {
			x = x*10 + int(c-'0')
		} else if c == '[' {
			stk = append(stk, &NestedInteger{})
		} else if c == ',' || c == ']' {
			if s[i-1] >= '0' && s[i-1] <= '9' {
				if neg {
					x = -x
				}
				t := NestedInteger{}
				t.SetInteger(x)
				stk[len(stk)-1].Add(t)
			}
			x = 0
			neg = false
			if c == ']' && len(stk) > 1 {
				t := stk[len(stk)-1]
				stk = stk[:len(stk)-1]
				stk[len(stk)-1].Add(*t)
			}
		}
	}
	return stk[0]
}