N=int(input())
a=0
for i in range(N+1):
    if i%2 != 0:
        a += 1
print(a/N) N=int(input()) N int(input()) int input() input a=0 a 0 for i in range(N+1):
    if i%2 != 0:
        a += 1 i range(N+1) range N+1 N 1 if i%2 != 0:
        a += 1 i%2 != 0 i%2 i 2 0 a += 1 a 1 print(a/N) print a/N a N a=0 0 a a += 1 1 a N=int(input()) int(input()) N
N=int(input())
a=0
for i in range(N+1):
    if i%2 != 0:
        a += 1
print(a/N)