n = int(input())

d = {0:1,1:1}
def calc(n):
    if n not in d:
        d[n] = calc(n-2)+calc(n-1)
    return d[n]

for i in range(n):
    calc(i)

print(calc(n)) n = int(input()) n int(input()) int input() input d = {0:1,1:1} d {0:1,1:1} 0 0 1 1 1 1 def calc(n):
    if n not in d:
        d[n] = calc(n-2)+calc(n-1)
    return d[n] calc if n not in d:
        d[n] = calc(n-2)+calc(n-1)
     n not in d n d d[n] = calc(n-2)+calc(n-1) d[n] d n calc(n-2)+calc(n-1) calc(n-2) calc n-2 n 2 calc(n-1) calc n-1 n 1 return d[n] d[n] d n n n for i in range(n):
    calc(i) i range(n) range n calc(i) calc i print(calc(n)) print calc(n) calc n def calc(n):
    if n not in d:
        d[n] = calc(n-2)+calc(n-1)
    return d[n] def calc(n):
    if n not in d:
        d[n] = calc(n-2)+calc(n-1)
    return d[n] calc d = {0:1,1:1} {0:1,1:1} d n = int(input()) int(input()) n
n = int(input())

d = {0:1,1:1}
def calc(n):
    if n not in d:
        d[n] = calc(n-2)+calc(n-1)
    return d[n]

for i in range(n):
    calc(i)

print(calc(n))
