n = float(input())
a = 2
b = 1
x = 0
sn = 0
while x < n: # a 和 b 作为中间变量传递numerator和denominator的值
numerator = a
denominator = b
#先将中间变量a,b的值分别赋给分子和分母
n = float(input())
a = 2
b = 1
x = 0
sn = 0
while x < n: # a 和 b 作为中间变量传递numerator和denominator的值
numerator = a
denominator = b
#先将中间变量a,b的值分别赋给分子和分母