import sys
import itertools
sys.setrecursionlimit(1000000000)
from heapq import heapify,heappop,heappush,heappushpop
import math
import collections
import copy

n = int(input())
dp = [0]*(1000001)
dp[0] = 1
dp[1] = 1
for i in range(2,n+1):
    dp[i] = dp[i-1] + dp[i-2]
print(dp[n]) import sys sys import itertools itertools sys.setrecursionlimit(1000000000) sys.setrecursionlimit sys setrecursionlimit 1000000000 from heapq import heapify,heappop,heappush,heappushpop import math math import collections collections import copy copy n = int(input()) n int(input()) int input() input dp = [0]*(1000001) dp [0]*(1000001) [0] 0 1000001 dp[0] = 1 dp[0] dp 0 1 dp[1] = 1 dp[1] dp 1 1 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 print(dp[n]) print dp[n] dp n dp = [0]*(1000001) [0]*(1000001) dp n = int(input()) int(input()) n
import sys
import itertools
sys.setrecursionlimit(1000000000)
from heapq import heapify,heappop,heappush,heappushpop
import math
import collections
import copy

n = int(input())
dp = [0]*(1000001)
dp[0] = 1
dp[1] = 1
for i in range(2,n+1):
    dp[i] = dp[i-1] + dp[i-2]
print(dp[n])
