# 1 1 2 3 5
list=[]
for i in range(100000):
list.append(0)
def feibo(n):
if n==1 or n==2:
return 1
if list[n]!=0:
return list[n]
else:
a=feibo(n-1)+feibo(n-2)
list[n]=a
return a
n=int(input())
b=feibo(n)
print(b%(10**9+7))