From d136b001b6d9590b268dd12aa936d1ad34915ebf Mon Sep 17 00:00:00 2001
From: "huangge1199@hotmail.com" <huangge1199>
Date: Tue, 27 Apr 2021 22:00:01 +0800
Subject: [PATCH] =?UTF-8?q?705:=E8=AE=BE=E8=AE=A1=E5=93=88=E5=B8=8C?=
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---
 .../leetcode/editor/cn/DesignHashset.java     | 104 ++++++++++++++++++
 .../java/leetcode/editor/cn/DesignHashset.md  |  44 ++++++++
 2 files changed, 148 insertions(+)
 create mode 100644 LeetCode/src/main/java/leetcode/editor/cn/DesignHashset.java
 create mode 100644 LeetCode/src/main/java/leetcode/editor/cn/DesignHashset.md

diff --git a/LeetCode/src/main/java/leetcode/editor/cn/DesignHashset.java b/LeetCode/src/main/java/leetcode/editor/cn/DesignHashset.java
new file mode 100644
index 0000000..7aa091d
--- /dev/null
+++ b/LeetCode/src/main/java/leetcode/editor/cn/DesignHashset.java
@@ -0,0 +1,104 @@
+//不使用任何内建的哈希表库设计一个哈希集合（HashSet）。 
+//
+// 实现 MyHashSet 类： 
+//
+// 
+// void add(key) 向哈希集合中插入值 key 。 
+// bool contains(key) 返回哈希集合中是否存在这个值 key 。 
+// void remove(key) 将给定值 key 从哈希集合中删除。如果哈希集合中没有这个值，什么也不做。 
+// 
+// 
+//
+// 示例： 
+//
+// 
+//输入：
+//["MyHashSet", "add", "add", "contains", "contains", "add", "contains", "remove
+//", "contains"]
+//[[], [1], [2], [1], [3], [2], [2], [2], [2]]
+//输出：
+//[null, null, null, true, false, null, true, null, false]
+//
+//解释：
+//MyHashSet myHashSet = new MyHashSet();
+//myHashSet.add(1);      // set = [1]
+//myHashSet.add(2);      // set = [1, 2]
+//myHashSet.contains(1); // 返回 True
+//myHashSet.contains(3); // 返回 False ，（未找到）
+//myHashSet.add(2);      // set = [1, 2]
+//myHashSet.contains(2); // 返回 True
+//myHashSet.remove(2);   // set = [1]
+//myHashSet.contains(2); // 返回 False ，（已移除） 
+//
+// 
+//
+// 提示： 
+//
+// 
+// 0 <= key <= 106 
+// 最多调用 104 次 add、remove 和 contains 。 
+// 
+//
+// 
+//
+// 进阶：你可以不使用内建的哈希集合库解决此问题吗？ 
+// Related Topics 设计 哈希表 
+// 👍 157 👎 0
+
+package leetcode.editor.cn;
+
+import java.util.ArrayList;
+import java.util.List;
+
+//705:设计哈希集合
+public class DesignHashset{
+    public static void main(String[] args) {
+        //测试代码
+//        Solution solution = new DesignHashset().new Solution();
+    }
+    //力扣代码
+    //leetcode submit region begin(Prohibit modification and deletion)
+class MyHashSet {
+        List<Integer> list;
+
+    /** Initialize your data structure here. */
+    public MyHashSet() {
+        list = new ArrayList<>();
+    }
+    
+    public void add(int key) {
+        if(list.contains(key)){
+            return;
+        }
+        list.add(key);
+    }
+    
+    public void remove(int key) {
+        for (int i = 0; i < list.size(); i++) {
+            if(list.get(i)==key){
+                list.remove(i);
+            }
+        }
+    }
+    
+    /** Returns true if this set contains the specified element */
+    public boolean contains(int key) {
+        for (int i = 0; i < list.size(); i++) {
+            if(list.get(i)==key){
+                return true;
+            }
+        }
+        return false;
+    }
+}
+
+/**
+ * Your MyHashSet object will be instantiated and called as such:
+ * MyHashSet obj = new MyHashSet();
+ * obj.add(key);
+ * obj.remove(key);
+ * boolean param_3 = obj.contains(key);
+ */
+//leetcode submit region end(Prohibit modification and deletion)
+
+}
\ No newline at end of file
diff --git a/LeetCode/src/main/java/leetcode/editor/cn/DesignHashset.md b/LeetCode/src/main/java/leetcode/editor/cn/DesignHashset.md
new file mode 100644
index 0000000..830a019
--- /dev/null
+++ b/LeetCode/src/main/java/leetcode/editor/cn/DesignHashset.md
@@ -0,0 +1,44 @@
+<p>不使用任何内建的哈希表库设计一个哈希集合（HashSet）。</p>
+
+<p>实现 <code>MyHashSet</code> 类：</p>
+
+<ul>
+	<li><code>void add(key)</code> 向哈希集合中插入值 <code>key</code> 。</li>
+	<li><code>bool contains(key)</code> 返回哈希集合中是否存在这个值 <code>key</code> 。</li>
+	<li><code>void remove(key)</code> 将给定值 <code>key</code> 从哈希集合中删除。如果哈希集合中没有这个值，什么也不做。</li>
+</ul>
+ 
+
+<p><strong>示例：</strong></p>
+
+<pre>
+<strong>输入：</strong>
+["MyHashSet", "add", "add", "contains", "contains", "add", "contains", "remove", "contains"]
+[[], [1], [2], [1], [3], [2], [2], [2], [2]]
+<strong>输出：</strong>
+[null, null, null, true, false, null, true, null, false]
+
+<strong>解释：</strong>
+MyHashSet myHashSet = new MyHashSet();
+myHashSet.add(1);      // set = [1]
+myHashSet.add(2);      // set = [1, 2]
+myHashSet.contains(1); // 返回 True
+myHashSet.contains(3); // 返回 False ，（未找到）
+myHashSet.add(2);      // set = [1, 2]
+myHashSet.contains(2); // 返回 True
+myHashSet.remove(2);   // set = [1]
+myHashSet.contains(2); // 返回 False ，（已移除）</pre>
+
+<p> </p>
+
+<p><strong>提示：</strong></p>
+
+<ul>
+	<li><code>0 <= key <= 10<sup>6</sup></code></li>
+	<li>最多调用 <code>10<sup>4</sup></code> 次 <code>add</code>、<code>remove</code> 和 <code>contains</code> 。</li>
+</ul>
+
+<p> </p>
+
+<p><strong>进阶：</strong>你可以不使用内建的哈希集合库解决此问题吗？</p>
+<div><div>Related Topics</div><div><li>设计</li><li>哈希表</li></div></div>\n<div><li>👍 157</li><li>👎 0</li></div>
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