enumerate is slightly faster than for

def plusMinus(arr): positives = 0 zeros = 0 negatives = 0 size = len(arr)

for number arr:
    if number > 0 :
        positives += 1
    elif number == 0 :
        zeros += 1
    else:
        negatives += 1

print(f'{positives/size:.6f}')
print(f'{negatives/size:.6f}')
print(f'{zeros/size:.6f}')

if name == 'main': n = int(input().strip())

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

plusMinus(arr)