diff --git a/best-time-to-buy-and-sell-stock/Hyeri1ee.java b/best-time-to-buy-and-sell-stock/Hyeri1ee.java
new file mode 100644
index 0000000000..757cac6ddb
--- /dev/null
+++ b/best-time-to-buy-and-sell-stock/Hyeri1ee.java
@@ -0,0 +1,41 @@
+class Solution {
+
+  
+   
+
+
+    //O(n)에 증가 한 경우 profitMax를 갱신시키며 판단 -> time limit
+    public int maxProfit(int[] prices) {
+        int profitMax = 0;
+        /*
+        for(int i=0; i< prices.length - 1; i++){
+            int buy= prices[i];
+        
+
+            for(int d =i+1; d < prices.length; d++){
+                int sellCandid = prices[d];
+                if (sellCandid - buy > profitMax){
+                    profitMax = sellCandid - buy;
+                }
+
+            }
+        }//end of for
+
+        */
+
+        int priceMin = Integer.MAX_VALUE;
+        for(int i =0; i < prices.length; i++){
+            if (prices[i] < priceMin){
+                priceMin = prices[i];
+            }
+            else{
+                profitMax = Math.max(profitMax, prices[i] - priceMin);
+            }
+        }
+
+        return profitMax; 
+        
+    }
+    
+}
+
diff --git a/group-anagrams/Hyeri1ee.java b/group-anagrams/Hyeri1ee.java
new file mode 100644
index 0000000000..d5fec4a6e2
--- /dev/null
+++ b/group-anagrams/Hyeri1ee.java
@@ -0,0 +1,30 @@
+import java.util.*;
+
+class Solution {
+    //static HashMap<
+    public List<List<String>> groupAnagrams(String[] strs) {
+        HashMap<String, List<String>> map  = new HashMap<>();
+
+        for(int w = 0 ;w < strs.length; w++){
+            String word = strs[w];
+            char[] arr = word.toCharArray();
+
+            //정렬한거
+            Arrays.sort(arr);
+            String newWord = new String(arr);
+
+            map.putIfAbsent(newWord, new ArrayList<>());
+            map.get(newWord).add(word);
+
+        }
+
+
+        List<List<String>> list = new ArrayList<>();
+        for(List<String> group : map.values()){
+            list.add(group);
+        }
+
+        return list;
+    }
+}
+