[백준] 2193번 : 이친수 - Python(파이썬)

https://www.acmicpc.net/problem/2193

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