Update 3. 数组中重复的数字.md

题目链接改为力扣中的对应题目，题目描述和代码按该题的接口调整。

notes/3. 数组中重复的数字.md

@@ -2,7 +2,7 @@
 
 ## 题目链接
 
-[牛客网](https://www.nowcoder.com/practice/6fe361ede7e54db1b84adc81d09d8524?tpId=13&tqId=11203&tab=answerKey&from=cyc_github)
+[Leetcode](https://leetcode.cn/problems/shu-zu-zhong-zhong-fu-de-shu-zi-lcof/)
 
 ## 题目描述
 
@@ -28,13 +28,13 @@ Output:
 
 
 ```java
-public int duplicate(int[] nums) {
-    for (int i = 0; i < nums.length; i++) {
-        while (nums[i] != i) {
-            if (nums[i] == nums[nums[i]]) {
-                return  nums[i];
+public int findRepeatDocument(int[] documents) {
+    for (int i = 0; i < documents.length; i++) {
+        while (documents[i] != i) {
+            if (documents[i] == documents[documents[i]]) {
+                return documents[i];
             }
-            swap(nums, i, nums[i]);
+            swap(documents, i, documents[i]);
         }
     }
     return -1;
@@ -45,6 +45,5 @@ private void swap(int[] nums, int i, int j) {
     nums[i] = nums[j];
     nums[j] = t;
 }
-
 ```