issue #16 217-Done

sowon-dev · sowon-dev · commit 59ea6573276b · 2021-01-26T00:06:55.000+09:00
diff --git a/src/leetcodeEasyLevel/_0217ContainsDuplicate.java b/src/leetcodeEasyLevel/_0217ContainsDuplicate.java
@@ -0,0 +1,51 @@
+package leetcodeEasyLevel;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Set;
+
+public class _0217ContainsDuplicate {
+  public static boolean containsDuplicate(int[] nums) {
+    //sol1 Runtime 5 ms Memory 46.2 MB
+    /*
+    Set<Integer> nSet = new HashSet<>();
+    boolean isDuplicated = false;
+
+    for(int i=0; i<nums.length; i++){
+      //add&#54616;&#47732;&#49436; &#51473;&#48373;&#46108; &#49707;&#51088;&#44032; &#51080;&#45716;&#51648; &#54869;&#51064;
+      if(!nSet.add(nums[i])){
+        isDuplicated = true;
+      }
+    }
+    return isDuplicated;
+*/
+    //sol2 Runtime 3 ms Memory 41.9 MB
+    /*
+    Arrays.sort(nums);
+    for(int i=0; i< nums.length-1; i++){
+      if(nums[i] == nums[i+1]) return true;
+    }
+    return false;
+    */
+
+    //sol3 Runtime 6 ms Memory 45.2 MB
+    Set<Integer> numSet = new HashSet<>();
+    for(int i:nums){
+      if(numSet.contains(i)){
+        return true;
+      } else {
+        numSet.add(i);
+      }
+    }
+    return false;
+  }
+
+  public static void main(String[] args) {
+    //int[] nums = {1,2,3,1};//=> true
+    int[] nums = {1,2,3,4};//=> false
+
+    System.out.println(containsDuplicate(nums));
+  }
+}
