MAX_N = 44
dp = [None] * (MAX_N + 1)
dp[0] = 1
dp[1] = 1

def fib(n):
    for i in range(2, n+1):
        dp[i] = dp[i-1] + dp[i-2]
    
    return dp[n]

n = int(input())
print(fib(n))
 MAX_N = 44 MAX_N 44 dp = [None] * (MAX_N + 1) dp [None] * (MAX_N + 1) [None] None MAX_N + 1 MAX_N 1 dp[0] = 1 dp[0] dp 0 1 dp[1] = 1 dp[1] dp 1 1 def fib(n):
    for i in range(2, n+1):
        dp[i] = dp[i-1] + dp[i-2]
    
    return dp[n] fib for i in range(2, n+1):
        dp[i] = dp[i-1] + dp[i-2]
    
     i range(2, n+1) range 2 n+1 n 1 dp[i] = dp[i-1] + dp[i-2] dp[i] dp i dp[i-1] + dp[i-2] dp[i-1] dp i-1 i 1 dp[i-2] dp i-2 i 2 return dp[n] dp[n] dp n n n n = int(input()) n int(input()) int input() input print(fib(n)) print fib(n) fib n dp = [None] * (MAX_N + 1) [None] * (MAX_N + 1) dp n = int(input()) int(input()) n def fib(n):
    for i in range(2, n+1):
        dp[i] = dp[i-1] + dp[i-2]
    
    return dp[n] def fib(n):
    for i in range(2, n+1):
        dp[i] = dp[i-1] + dp[i-2]
    
    return dp[n] fib MAX_N = 44 44 MAX_N
MAX_N = 44
dp = [None] * (MAX_N + 1)
dp[0] = 1
dp[1] = 1

def fib(n):
    for i in range(2, n+1):
        dp[i] = dp[i-1] + dp[i-2]
    
    return dp[n]

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

