
fibo_list=[0 for i in range(48)]

def fibo(n):
    f=fibo_list[n]
    if f:
        return f
    else:
        if n==0 or n==1:
            return 1
        else:
            f=fibo(n-1)+(fibo(n-2))
    fibo_list[n]=f
    return f


n=input()
print(fibo(n)) 0 for i in range(48) for i in range(48) i range(48) range 48 for i in range(48) 0 fibo_list=[0 for i in range(48)] fibo_list [0 for i in range(48)] def fibo(n):
    f=fibo_list[n]
    if f:
        return f
    else:
        if n==0 or n==1:
            return 1
        else:
            f=fibo(n-1)+(fibo(n-2))
    fibo_list[n]=f
    return f fibo f=fibo_list[n] f fibo_list[n] fibo_list n if f:
        return f
    else:
        if n==0 or n==1:
            return 1
        else:
            f=fibo(n-1)+(fibo(n-2))
     f return f f if n==0 or n==1:
            return 1
        else:
            f=fibo(n-1)+(fibo(n-2))
     n==0 or n==1 n==0 n 0 n==1 n 1 return 1 1 f=fibo(n-1)+(fibo(n-2)) f fibo(n-1)+(fibo(n-2)) fibo(n-1) fibo n-1 n 1 fibo(n-2) fibo n-2 n 2 fibo_list[n]=f fibo_list[n] fibo_list n f return f f n n n=input() n input() input print(fibo(n)) print fibo(n) fibo n fibo_list=[0 for i in range(48)] [0 for i in range(48)] fibo_list n=input() input() n def fibo(n):
    f=fibo_list[n]
    if f:
        return f
    else:
        if n==0 or n==1:
            return 1
        else:
            f=fibo(n-1)+(fibo(n-2))
    fibo_list[n]=f
    return f def fibo(n):
    f=fibo_list[n]
    if f:
        return f
    else:
        if n==0 or n==1:
            return 1
        else:
            f=fibo(n-1)+(fibo(n-2))
    fibo_list[n]=f
    return f fibo

fibo_list=[0 for i in range(48)]

def fibo(n):
    f=fibo_list[n]
    if f:
        return f
    else:
        if n==0 or n==1:
            return 1
        else:
            f=fibo(n-1)+(fibo(n-2))
    fibo_list[n]=f
    return f


n=input()
print(fibo(n))