Solve : climbing-Stairs

Author: printjin-gmailcom

climbing-stairs/printjin-gmailcom.py

@@ -0,0 +1,8 @@
+class Solution:
+    def climbStairs(self, n: int):
+        if n <= 2:      
+            return n
+        a, b = 1, 2
+        for _ in range(3, n+1):
+            a, b = b, a + b
+        return b