slice.go

type Slice struct {
	Data     []int
	Length   int
	Capacity int
}

func Insert(record *Slice, position int, value int) {
	capacity := record.Length + 1
	if position > capacity {
		capacity = position
	}

	CheckLength(record, capacity)
	record.Length++

	for i := record.Length; i >= position; i-- {
		record.Data[i] = record.Data[i-1]
	}

	record.Data[position] = value
}

func CheckLength(record *Slice, length int) {
	if length <= record.Capacity {
		return
	}

	capacity := record.Capacity << 1
	if capacity < length {
		capacity = length
	}

	data := make([]int, capacity)
	for i := 0; i < record.Length; i++ {
		data[i] = record.Data[i]
	}

	record.Data = data
	record.Capacity = capacity
}