feat: solve climbing-stairs

Author: lylaminju

climbing-stairs/pmjuu.py

@@ -0,0 +1,17 @@
+class Solution:
+    def climbStairs(self, n: int) -> int:
+        # dp[i] represents the number of distinct ways to climb to the ith step.
+        # Base cases:
+        # - There is 1 way to reach step 0 (doing nothing).
+        # - There is 1 way to reach step 1 (a single step).
+        dp = [0] * (n + 1)
+        dp[0], dp[1] = 1, 1
+
+        for i in range(2, n + 1):
+            dp[i] = dp[i - 1] + dp[i - 2]
+        
+        return dp[n]
+    
+# Complexity
+# - time: O(n)
+# - space: O(n)