n = int(input())
data = []
x = []

if n == 0:
    print('1')
data.append(1)
if n == 1:
    print('1')
data.append(1)

if n >= 2:
    for i in range(2, n+1):
    #print(sum(data[i-2:i+1]))
    #print(data[1])
    #data.append(data[i])
        x = sum(data[i-2:i+1])
        data.append(x)
    #print(i, x)
        i = i + 1
    print(x) n = int(input()) n int(input()) int input() input data = [] data [] x = [] x [] if n == 0:
    print('1') n == 0 n 0 print('1') print '1' data.append(1) data.append data append 1 if n == 1:
    print('1') n == 1 n 1 print('1') print '1' data.append(1) data.append data append 1 if n >= 2:
    for i in range(2, n+1):
    #print(sum(data[i-2:i+1]))
    #print(data[1])
    #data.append(data[i])
        x = sum(data[i-2:i+1])
        data.append(x)
    #print(i, x)
        i = i + 1
    print(x) n >= 2 n 2 for i in range(2, n+1):
    #print(sum(data[i-2:i+1]))
    #print(data[1])
    #data.append(data[i])
        x = sum(data[i-2:i+1])
        data.append(x)
    #print(i, x)
        i = i + 1
     i range(2, n+1) range 2 n+1 n 1 x = sum(data[i-2:i+1]) x sum(data[i-2:i+1]) sum data[i-2:i+1] data i-2:i+1 i-2 i 2 i+1 i 1 data.append(x) data.append data append x i = i + 1 i i + 1 i 1 print(x) print x x = sum(data[i-2:i+1]) sum(data[i-2:i+1]) x n = int(input()) int(input()) n data = [] [] data x = [] [] x i = i + 1 i + 1 i
n = int(input())
data = []
x = []

if n == 0:
    print('1')
data.append(1)
if n == 1:
    print('1')
data.append(1)

if n >= 2:
    for i in range(2, n+1):
    #print(sum(data[i-2:i+1]))
    #print(data[1])
    #data.append(data[i])
        x = sum(data[i-2:i+1])
        data.append(x)
    #print(i, x)
        i = i + 1
    print(x)
