# bottom-up
def fibo(n):
    arr = [0] * (n + 1)
    arr[1] = 1
    for i in xrange(2, n + 1):
        arr[i] = arr[i - 1] + arr[i - 2]

    return arr[n]

# Top Down


def fibonacci(n, arr):
    if n == 0 or n == 1:
        arr[n] = n

    if arr[n] is None:
        arr[n] = fibonacci(n - 1, arr) + fibonacci(n - 2, arr)

    return arr[n]


def main():
    '''n = int(raw_input())
    print "Fibonacci of the Given Number", fibo(n)'''
    n = int(raw_input())
    arr = [None] * 100
    print "Fibonacci  of The Given Number", fibonacci(n, arr)

if __name__ == '__main__':
    main()
