n=int(eval(input()))

arr=list(map(int,input().split()))

sum1=1

for val in arr:

  sum1*=val

sum2=0

for i in range(n):

  tmp=1

  for j in range(n):

    if i==j:

      continue

    tmp*=arr[j]

  sum2+=tmp

print((sum1/sum2))
n=int(eval(input()))

arr=list(map(int,input().split()))

sums=0

for val in arr:

  sums+=1.0/val

print((1.0/sums))
n = int(eval(input()))
arr = list(map(int, input().split()))
sum1 = 1
for val in arr:
    sum1 *= val
sum2 = 0
for i in range(n):
    tmp = 1
    for j in range(n):
        if i == j:
            continue
        tmp *= arr[j]
    sum2 += tmp
print((sum1 / sum2))

n = int(eval(input()))
arr = list(map(int, input().split()))
sums = 0
for val in arr:
    sums += 1.0 / val
print((1.0 / sums))

-sum1 = 1 +sums = 0 -    sum1 *= val -sum2 = 0 -for i in range(n): -    tmp = 1 -    for j in range(n): -        if i == j: -            continue -        tmp *= arr[j] -    sum2 += tmp -print((sum1 / sum2)) +    sums += 1.0 / val +print((1.0 / sums))