It is November 18 now in Japan. By the way, 11 and 18 are adjacent Lucas numbers.  You are given an integer N. Find the N-th Lucas number.  Here, the i-th Lucas number L_i is defined as follows:    * L_0=2   * L_1=1   * L_i=L_{i-1}+L_{i-2} (i≥2)
n = int(input())
tb = [0] * max(3, (n + 1))
tb[1] = 2
tb[2] = 1

if n > 2:
  for i in range(3, n+1):
    tb[i] = tb[i - 1] + tb[i - 2] 

print(tb[n])

n = int(input())
tb = [0] * max(3, (n + 1))
tb[0] = 2
tb[1] = 1

if n > 1:
  for i in range(2, n+1):
    tb[i] = tb[i - 1] + tb[i - 2] 

print(tb[n])
