feat: climbing-stairs

Author: minji-go

climbing-stairs/minji-go.java

@@ -1,21 +1,24 @@
-/*
-    Problem: https://leetcode.com/problems/climbing-stairs/
-    Description: how many distinct ways can you climb to the top, if you can either climb 1 or 2 steps
-    Concept: Dynamic Programming, Memoization, Recursion, Math, Array, Iterator, Combinatorics ...
-    Time Complexity: O(n), Runtime: 0ms
-    Space Complexity: O(1), Memory: 40.63MB
-*/
+/**
+ * <a href="https://leetcode.com/problems/climbing-stairs/">week02-2.climbing-stairs</a>
+ * <li> Description: how many distinct ways can you climb to the top, if you can either climb 1 or 2 steps  </li>
+ * <li> Concept: Dynamic Programming, Memoization, Recursion, Math, Array, Iterator, Combinatorics ...      </li>
+ * <li> Time Complexity: O(n), Runtime: 0ms     </li>
+ * <li> Space Complexity: O(1), Memory: 40.39MB </li>
+ */
+
 class Solution {
     public int climbStairs(int n) {
-        if(n==1) return 1;
-        if(n==2) return 2;
+        if (n <= 2) return n;
+
+        int prev = 1;
+        int curr = 2;
 
-        int prev=1, cur=2;
-        for(int i=3; i<=n; i++){
-            int next=prev+cur;
-            prev=cur;
-            cur=next;
+        for (int i = 3; i <= n; i++) {
+            int next = prev + curr;
+            prev = curr;
+            curr = next;
         }
-        return cur;
+
+        return curr;
     }
 }

valid-anagram/minji-go.java

@@ -20,4 +20,4 @@ public boolean isAnagram(String s, String t) {
 
         return tmap.equals(smap);
     }
-}
+}