package main

import ("fmt")

type Solution struct{
	dp map[[2]int]float64
}

func NewSolution() *Solution{
	return &Solution{dp: make(map[[2]int]float64)}
}

func (s *Solution) SoupServings(n int)float64{
	if n > 5000{
		return 1.0
	}

	n = (n+24) /25

	return s.helper(n, n)
}

func (s * Solution) helper(a, b int) float64 {
	if a <= 0 && b <= 0{
		return 0.5
	}
	if a <= 0{
		return 1.0
	}
	if b <= 0{
		return 0
	}

	if val, exist := s.dp[[2]int{a, b}]; exist{
		return val
	}

	probability := 0.25 * (
		s.helper(a-4, b) +
		s.helper(a-3, b-1) +
		s.helper(a-2, b-2) +
		s.helper(a-1, b-3))

	s.dp[[2]int {a, b}] = probability
	return probability
}

func main(){
	Solution := NewSolution()
	ans := Solution.SoupServings(100)
	fmt.Println(ans)
}