# coding: utf-8
# Your code here!

n = int(input())
m = [1,1]
if n == 0:
    print(1)
elif n == 1:
    print(1)
else:
    for i in range(2, n+1):
        m.append( m[i-1] + m[i-2] )
    print(m.pop()) n = int(input()) n int(input()) int input() input m = [1,1] m [1,1] 1 1 if n == 0:
    print(1)
elif n == 1:
    print(1)
else:
    for i in range(2, n+1):
        m.append( m[i-1] + m[i-2] )
    print(m.pop()) n == 0 n 0 print(1) print 1 elif n == 1:
    print(1) n == 1 n 1 print(1) print 1 for i in range(2, n+1):
        m.append( m[i-1] + m[i-2] )
     i range(2, n+1) range 2 n+1 n 1 m.append( m[i-1] + m[i-2] ) m.append m append m[i-1] + m[i-2] m[i-1] m i-1 i 1 m[i-2] m i-2 i 2 print(m.pop()) print m.pop() m.pop m pop m = [1,1] [1,1] m n = int(input()) int(input()) n
# coding: utf-8
# Your code here!

n = int(input())
m = [1,1]
if n == 0:
    print(1)
elif n == 1:
    print(1)
else:
    for i in range(2, n+1):
        m.append( m[i-1] + m[i-2] )
    print(m.pop())
