contains-duplicate Set 방식으로 변경

Author: mintheon

contains-duplicate/mintheon.java

@@ -1,13 +1,14 @@
-import java.util.Arrays;
+import java.util.HashSet;
+import java.util.Set;
 
 class Solution {
   public boolean containsDuplicate(int[] nums) {
-    Arrays.sort(nums);
-    for(int i = 1; i < nums.length; i++) {
-      if(nums[i] == nums[i - 1]) {
-        return true;
-      }
+    Set<Integer> numSet = new HashSet();
+
+    for(int num : nums) {
+      numSet.add(num);
     }
-    return false;
+
+    return numSet.size() != nums.length;
   }
 }