F =[1,1] + [0 for i in range(44)]

n = int(input())

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

print(F[n]) 0 for i in range(44) for i in range(44) i range(44) range 44 for i in range(44) 0 F =[1,1] + [0 for i in range(44)] F [1,1] + [0 for i in range(44)] [1,1] 1 1 [0 for i in range(44)] n = int(input()) n int(input()) int input() input for i in range(2,n+1):
  F[i]=F[i-1]+F[i-2] i range(2,n+1) range 2 n+1 n 1 F[i]=F[i-1]+F[i-2] F[i] F i F[i-1]+F[i-2] F[i-1] F i-1 i 1 F[i-2] F i-2 i 2 print(F[n]) print F[n] F n n = int(input()) int(input()) n F =[1,1] + [0 for i in range(44)] [1,1] + [0 for i in range(44)] F
F =[1,1] + [0 for i in range(44)]

n = int(input())

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

print(F[n])