n = int(input())

if n % 2 == 0:
    print(f'{(n/2) / n:.10f}')
else:
    print(f'{(n//2 + 1) / n:.10f}') n = int(input()) n int(input()) int input() input if n % 2 == 0:
    print(f'{(n/2) / n:.10f}')
else:
    print(f'{(n//2 + 1) / n:.10f}') n % 2 == 0 n % 2 n 2 0 print(f'{(n/2) / n:.10f}') print f'{(n/2) / n:.10f}' print(f'{(n//2 + 1) / n:.10f}') print f'{(n//2 + 1) / n:.10f}' n = int(input()) int(input()) n
n = int(input())

if n % 2 == 0:
    print(f'{(n/2) / n:.10f}')
else:
    print(f'{(n//2 + 1) / n:.10f}')
