From 21149f1fdd50e0c49dca7d550f19ddfe13d2923a Mon Sep 17 00:00:00 2001
From: Zhoutianyu <1941587995@qq.com>
Date: Wed, 29 Apr 2026 18:32:48 +0800
Subject: [PATCH] =?UTF-8?q?=E6=B7=BB=E5=8A=A0=20'w8'?=
MIME-Version: 1.0
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---
 w8 | 31 +++++++++++++++++++++++++++++++
 1 file changed, 31 insertions(+)
 create mode 100644 w8

diff --git a/w8 b/w8
new file mode 100644
index 0000000..36639ed
--- /dev/null
+++ b/w8
@@ -0,0 +1,31 @@
+public class Pair<K, V> {
+    private K key;
+    private V value;
+
+    public Pair(K key, V value) {
+        this.key = key;
+        this.value = value;
+    }
+
+    public K getKey() { return key; }
+    public V getValue() { return value; }
+
+    // swap：交换后原key变value，原value变key，返回新Pair
+    public Pair<V, K> swap() {
+        return new Pair<>(value, key);
+    }
+}
+
+
+import java.util.concurrent.ConcurrentHashMap;
+
+public class Cache<K, V> {
+    private final ConcurrentHashMap<K, V> cache = new ConcurrentHashMap<>();
+
+    public void put(K key, V value) { cache.put(key, value); }
+    public V get(K key) { return cache.get(key); }
+    public V remove(K key) { return cache.remove(key); }
+    public void clear() { cache.clear(); }
+    public int size() { return cache.size(); }
+    public boolean containsKey(K key) { return cache.containsKey(key); }
+}
\ No newline at end of file