# Arup Guha
# 7/14/2014
# Solution to SI@UCF Program: Fibonacci Numbers

def main():

    f1 = 1
    f2 = 1

    n = int(input("Which Fibonacci number do you want?\n"))

    # Take care of base cases.
    if n == 0:
        print("Fib(",n,") = 0", sep="")
    elif n < 3:
        print("Fib(",n,") = 1", sep="")

    else:

        # Store last two in f1, f2 and add!
        fcur = 0
        for i in range(3,n+1):
            fcur = f1 + f2
            f1 = f2
            f2 = fcur

        # Print end result.
        print("Fib(", n, ") = ", fcur, sep="")

main()