# coding=utf-8

def fib(n):
    global fib_list
    if fib_list[n]:
        return fib_list[n]

    if n == 0:
        fib_list[0] = 1
        return 1
    elif n == 1:
        fib_list[1] = 1
        return 1
    else:
        fib_list[n] = fib(n-2) + fib(n-1)
        return fib(n-2) + fib(n-1)

n = int(input())
fib_list = [None for i in range(n+1)]
print(fib(n)) def fib(n):
    global fib_list
    if fib_list[n]:
        return fib_list[n]

    if n == 0:
        fib_list[0] = 1
        return 1
    elif n == 1:
        fib_list[1] = 1
        return 1
    else:
        fib_list[n] = fib(n-2) + fib(n-1)
        return fib(n-2) + fib(n-1) fib global fib_list if fib_list[n]:
        return fib_list[n]

     fib_list[n] fib_list n return fib_list[n] fib_list[n] fib_list n if n == 0:
        fib_list[0] = 1
        return 1
    elif n == 1:
        fib_list[1] = 1
        return 1
    else:
        fib_list[n] = fib(n-2) + fib(n-1)
        return fib(n-2) + fib(n-1) n == 0 n 0 fib_list[0] = 1 fib_list[0] fib_list 0 1 return 1 1 elif n == 1:
        fib_list[1] = 1
        return 1
     n == 1 n 1 fib_list[1] = 1 fib_list[1] fib_list 1 1 return 1 1 fib_list[n] = fib(n-2) + fib(n-1) fib_list[n] fib_list n fib(n-2) + fib(n-1) fib(n-2) fib n-2 n 2 fib(n-1) fib n-1 n 1 return fib(n-2) + fib(n-1) fib(n-2) + fib(n-1) fib(n-2) fib n-2 n 2 fib(n-1) fib n-1 n 1 n n n = int(input()) n int(input()) int input() input None for i in range(n+1) for i in range(n+1) i range(n+1) range n+1 n 1 for i in range(n+1) None fib_list = [None for i in range(n+1)] fib_list [None for i in range(n+1)] print(fib(n)) print fib(n) fib n n = int(input()) int(input()) n def fib(n):
    global fib_list
    if fib_list[n]:
        return fib_list[n]

    if n == 0:
        fib_list[0] = 1
        return 1
    elif n == 1:
        fib_list[1] = 1
        return 1
    else:
        fib_list[n] = fib(n-2) + fib(n-1)
        return fib(n-2) + fib(n-1) def fib(n):
    global fib_list
    if fib_list[n]:
        return fib_list[n]

    if n == 0:
        fib_list[0] = 1
        return 1
    elif n == 1:
        fib_list[1] = 1
        return 1
    else:
        fib_list[n] = fib(n-2) + fib(n-1)
        return fib(n-2) + fib(n-1) fib fib_list = [None for i in range(n+1)] [None for i in range(n+1)] fib_list
# coding=utf-8

def fib(n):
    global fib_list
    if fib_list[n]:
        return fib_list[n]

    if n == 0:
        fib_list[0] = 1
        return 1
    elif n == 1:
        fib_list[1] = 1
        return 1
    else:
        fib_list[n] = fib(n-2) + fib(n-1)
        return fib(n-2) + fib(n-1)

n = int(input())
fib_list = [None for i in range(n+1)]
print(fib(n))