上传文件至 'w8'

w8/Pair.java

@@ -0,0 +1,29 @@
+package w8;
+
+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;
+    }
+    public static <k,v> Pair<v,k> swap(Pair<k,v> pair){
+        return new Pair<>(pair.getvalue(),pair.getkey());
+    }
+}
+class PairTest {
+    public static void main(String[] args) {
+        Pair<Integer,String> pair=new Pair<>(1,"a");
+        System.out.println(pair.getkey());
+        System.out.println(pair.getvalue());
+        Pair<String,Integer> pair2=Pair.swap(pair);
+        System.out.println(pair2.getkey());
+        System.out.println(pair2.getvalue());
+    }
+}