memoFib.go

func memoFib(num int, d map[int]int) int  {
	if num <= 1 {return 0}
	if num == 2 {return 1}
	if val, ok := d[num]; ok {
		return val
	}
	d[num] = memoFib(num-1,d)+memoFib(num-2,d)
	return d[num]
}