Solution for Valid Anagram #218

Author: dohyeon2

valid-anagram/dohyeon2.java

@@ -0,0 +1,26 @@
+import java.util.HashMap;
+
+class Solution {
+    public boolean isAnagram(String s, String t) {
+        if (s.length() != t.length()) {
+            return false;
+        }
+
+        // TC = O(n)
+        // SC = O(n)
+        HashMap<Character, Integer> sMap = new HashMap<>();
+
+        for (char c : s.toCharArray()) {
+            sMap.merge(c, 1, Integer::sum);
+        }
+
+        for (char c : t.toCharArray()) {
+            if (sMap.getOrDefault(c, 0) == 0) {
+                return false;
+            }
+            sMap.merge(c, -1, Integer::sum);
+        }
+
+        return true;
+    }
+}