Time: 0 ms (100.00%), Space: 6.4 MB (59.54%) - LeetHub

Author: knockcat

0070-climbing-stairs/0070-climbing-stairs.cpp

@@ -0,0 +1,19 @@
+class Solution {
+public:
+    int climbStairs(int n) {
+        
+        if(n == 1)
+            return 1;
+        
+        int prev2 = 1, prev = 1, res = 1;
+        
+        for(int i = 2; i <= n; ++i)
+        {
+            res = prev2 + prev;
+            prev = prev2;
+            prev2 = res;
+        }
+        
+        return res;
+    }
+};