def fib(n):
  if n==0 or n==1:
    return 1
  
  x=[1,1]
  for i in range(2,n+1):
    x.append(x[i-1]+x[i-2])

  return x[-1]

print(fib(int(input())))
 def fib(n):
  if n==0 or n==1:
    return 1
  
  x=[1,1]
  for i in range(2,n+1):
    x.append(x[i-1]+x[i-2])

  return x[-1] fib if n==0 or n==1:
    return 1
  
   n==0 or n==1 n==0 n 0 n==1 n 1 return 1 1 x=[1,1] x [1,1] 1 1 for i in range(2,n+1):
    x.append(x[i-1]+x[i-2])

   i range(2,n+1) range 2 n+1 n 1 x.append(x[i-1]+x[i-2]) x.append x append x[i-1]+x[i-2] x[i-1] x i-1 i 1 x[i-2] x i-2 i 2 return x[-1] x[-1] x -1 n n print(fib(int(input()))) print fib(int(input())) fib int(input()) int input() input def fib(n):
  if n==0 or n==1:
    return 1
  
  x=[1,1]
  for i in range(2,n+1):
    x.append(x[i-1]+x[i-2])

  return x[-1] def fib(n):
  if n==0 or n==1:
    return 1
  
  x=[1,1]
  for i in range(2,n+1):
    x.append(x[i-1]+x[i-2])

  return x[-1] fib
def fib(n):
  if n==0 or n==1:
    return 1
  
  x=[1,1]
  for i in range(2,n+1):
    x.append(x[i-1]+x[i-2])

  return x[-1]

print(fib(int(input())))

