
f = [-1]*45
f[0]=1
f[1]=1

def fib(i):
    global f

    if i<=1:
        return f[i]
    if f[i] == -1:
        f[i] = fib(i-1)+fib(i-2)
    return f[i]

n=int(input())
print(fib(n)) f = [-1]*45 f [-1]*45 [-1] -1 45 f[0]=1 f[0] f 0 1 f[1]=1 f[1] f 1 1 def fib(i):
    global f

    if i<=1:
        return f[i]
    if f[i] == -1:
        f[i] = fib(i-1)+fib(i-2)
    return f[i] fib global f if i<=1:
        return f[i]
     i<=1 i 1 return f[i] f[i] f i if f[i] == -1:
        f[i] = fib(i-1)+fib(i-2)
     f[i] == -1 f[i] f i -1 f[i] = fib(i-1)+fib(i-2) f[i] f i fib(i-1)+fib(i-2) fib(i-1) fib i-1 i 1 fib(i-2) fib i-2 i 2 return f[i] f[i] f i i i n=int(input()) n int(input()) int input() input print(fib(n)) print fib(n) fib n n=int(input()) int(input()) n def fib(i):
    global f

    if i<=1:
        return f[i]
    if f[i] == -1:
        f[i] = fib(i-1)+fib(i-2)
    return f[i] def fib(i):
    global f

    if i<=1:
        return f[i]
    if f[i] == -1:
        f[i] = fib(i-1)+fib(i-2)
    return f[i] fib f = [-1]*45 [-1]*45 f

f = [-1]*45
f[0]=1
f[1]=1

def fib(i):
    global f

    if i<=1:
        return f[i]
    if f[i] == -1:
        f[i] = fib(i-1)+fib(i-2)
    return f[i]

n=int(input())
print(fib(n))
