[LeetCode] Climbing Stairs 파이썬 (DP)

 28ms

class Solution:
    def climbStairs(self, n: int) -> int:
        
        if n == 1:
            return 1
        elif n == 2:
            return 2
        else:
            dp = [0]*(n+1)
            dp[1] = 1
            dp[2] = 2
            for i in range(3, n+1):
                dp[i] = dp[i-1] + dp[i-2]
            return dp[n]

 

swap 사용

32 ms

if n == 1:
    return 1
a, b = 1, 2
for i in range(2, n):
    a, b = b, a + b
return b