n = int(input())

l = [1,1]

if n in [0,1]:
    print(1)
else:
    for i in range(2, n+1):
        fib = l[-1] + l[-2]
        l.append(fib)
    print(fib)

 n = int(input()) n int(input()) int input() input l = [1,1] l [1,1] 1 1 if n in [0,1]:
    print(1)
else:
    for i in range(2, n+1):
        fib = l[-1] + l[-2]
        l.append(fib)
    print(fib) n in [0,1] n [0,1] 0 1 print(1) print 1 for i in range(2, n+1):
        fib = l[-1] + l[-2]
        l.append(fib)
     i range(2, n+1) range 2 n+1 n 1 fib = l[-1] + l[-2] fib l[-1] + l[-2] l[-1] l -1 l[-2] l -2 l.append(fib) l.append l append fib print(fib) print fib l = [1,1] [1,1] l n = int(input()) int(input()) n fib = l[-1] + l[-2] l[-1] + l[-2] fib
n = int(input())

l = [1,1]

if n in [0,1]:
    print(1)
else:
    for i in range(2, n+1):
        fib = l[-1] + l[-2]
        l.append(fib)
    print(fib)


