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


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


n = int(input())
F = [None]*(n + 1)
print(fibonacci(n))