fib = [1 for i in range(45)]
for i in range(2, 45):
    fib[i] = fib[i - 1] + fib[i - 2]
i = int(input())
print(fib[i]) 1 for i in range(45) for i in range(45) i range(45) range 45 for i in range(45) 1 fib = [1 for i in range(45)] fib [1 for i in range(45)] for i in range(2, 45):
    fib[i] = fib[i - 1] + fib[i - 2] i range(2, 45) range 2 45 fib[i] = fib[i - 1] + fib[i - 2] fib[i] fib i fib[i - 1] + fib[i - 2] fib[i - 1] fib i - 1 i 1 fib[i - 2] fib i - 2 i 2 i = int(input()) i int(input()) int input() input print(fib[i]) print fib[i] fib i i = int(input()) int(input()) i fib = [1 for i in range(45)] [1 for i in range(45)] fib
fib = [1 for i in range(45)]
for i in range(2, 45):
    fib[i] = fib[i - 1] + fib[i - 2]
i = int(input())
print(fib[i])