def fib(n):
    if n == 0 or n == 1:
        return 1
    if A[n] is not None:
        return A[n]
    A[n] = fib(n - 1) + fib(n - 2)
    return A[n]


A = [None] * (44 + 1)
n = int(input())
print(fib(n)) def fib(n):
    if n == 0 or n == 1:
        return 1
    if A[n] is not None:
        return A[n]
    A[n] = fib(n - 1) + fib(n - 2)
    return A[n] fib if n == 0 or n == 1:
        return 1
     n == 0 or n == 1 n == 0 n 0 n == 1 n 1 return 1 1 if A[n] is not None:
        return A[n]
     A[n] is not None A[n] A n None return A[n] A[n] A n A[n] = fib(n - 1) + fib(n - 2) A[n] A n fib(n - 1) + fib(n - 2) fib(n - 1) fib n - 1 n 1 fib(n - 2) fib n - 2 n 2 return A[n] A[n] A n n n A = [None] * (44 + 1) A [None] * (44 + 1) [None] None 44 + 1 44 1 n = int(input()) n int(input()) int input() input print(fib(n)) print fib(n) fib n def fib(n):
    if n == 0 or n == 1:
        return 1
    if A[n] is not None:
        return A[n]
    A[n] = fib(n - 1) + fib(n - 2)
    return A[n] def fib(n):
    if n == 0 or n == 1:
        return 1
    if A[n] is not None:
        return A[n]
    A[n] = fib(n - 1) + fib(n - 2)
    return A[n] fib n = int(input()) int(input()) n A = [None] * (44 + 1) [None] * (44 + 1) A
def fib(n):
    if n == 0 or n == 1:
        return 1
    if A[n] is not None:
        return A[n]
    A[n] = fib(n - 1) + fib(n - 2)
    return A[n]


A = [None] * (44 + 1)
n = int(input())
print(fib(n))