func main()
	var n: int :: cui@inputInt()
	var p: float :: cui@inputFloat()
	var ps: []float :: sieve(n, p)
	var ans: float :: 0.0
	for i(2, n)
		do ans :+ ps[i]
	end for
	do cui@print("\{ans}\n")
	func sieve(n: int, p: float): []float
		if(n < 2)
			ret[0.0].repeat(n + 1)
		end if
		var res: []float :: [1.0].repeat(n + 1)
		for i(2, n)
			var j: int :: 2 * i
			while(j <= n)
				do res[j] :* 1.0 - p
				do j :+ i
			end while
		end for
		ret res
	end func
end func