n=int(input())
a,b=1,1
if n<=1:
    print(1)
else:
    for i in range(n-1):
        c=a+b
        a=b
        b=c
    print(c) n=int(input()) n int(input()) int input() input a,b=1,1 a 1 b 1 if n<=1:
    print(1)
else:
    for i in range(n-1):
        c=a+b
        a=b
        b=c
    print(c) n<=1 n 1 print(1) print 1 for i in range(n-1):
        c=a+b
        a=b
        b=c
     i range(n-1) range n-1 n 1 c=a+b c a+b a b a=b a b b=c b c print(c) print c b=1,1 1 b a=b b a a,b=1,1 1 a n=int(input()) int(input()) n b=c c b c=a+b a+b c
n=int(input())
a,b=1,1
if n<=1:
    print(1)
else:
    for i in range(n-1):
        c=a+b
        a=b
        b=c
    print(c)
