import sys
if __name__ == "__main__":
    n = int(input())
    if n == 0 or n == 1:
        print(1)
        sys.exit(0)
    dp = [0] * (n + 1)
    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 if __name__ == "__main__":
    n = int(input())
    if n == 0 or n == 1:
        print(1)
        sys.exit(0)
    dp = [0] * (n + 1)
    dp[0] = 1
    dp[1] = 1
    for i in range(2, n + 1):
        dp[i] = dp[i - 1] + dp[i - 2]
    print(dp[n]) __name__ == "__main__" __name__ "__main__" n = int(input()) n int(input()) int input() input if n == 0 or n == 1:
        print(1)
        sys.exit(0)
     n == 0 or n == 1 n == 0 n 0 n == 1 n 1 print(1) print 1 sys.exit(0) sys.exit sys exit 0 dp = [0] * (n + 1) dp [0] * (n + 1) [0] 0 n + 1 n 1 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] * (n + 1) [0] * (n + 1) dp n = int(input()) int(input()) n
import sys
if __name__ == "__main__":
    n = int(input())
    if n == 0 or n == 1:
        print(1)
        sys.exit(0)
    dp = [0] * (n + 1)
    dp[0] = 1
    dp[1] = 1
    for i in range(2, n + 1):
        dp[i] = dp[i - 1] + dp[i - 2]
    print(dp[n])
