三刷26

Author: diguage

docs/0026-remove-duplicates-from-sorted-array.adoc

@@ -1,69 +1,94 @@
 [#0026-remove-duplicates-from-sorted-array]
-= 26. Remove Duplicates from Sorted Array
+= 26. 删除有序数组中的重复项
 
-{leetcode}/problems/remove-duplicates-from-sorted-array/[LeetCode - Remove Duplicates from Sorted Array^]
+https://leetcode.cn/problems/remove-duplicates-from-sorted-array/[LeetCode - 26. 删除有序数组中的重复项 ^]
 
-Given a sorted array _nums_, remove the duplicates https://en.wikipedia.org/wiki/In-place_algorithm[*in-place*^] such that each element appear only _once_ and return the new length.
+给你一个 *非严格递增排列* 的数组 `nums` ，请你 *http://baike.baidu.com/item/%E5%8E%9F%E5%9C%B0%E7%AE%97%E6%B3%95[原地]* 删除重复出现的元素，使每个元素 *只出现一次*，返回删除后数组的新长度。元素的 *相对顺序* 应该保持 *一致* 。然后返回 `nums` 中唯一元素的个数。
 
-Do not allocate extra space for another array, you must do this by *modifying the input array https://en.wikipedia.org/wiki/In-place_algorithm[in-place^]* with O(1) extra memory.
+考虑 `nums` 的唯一元素的数量为 `k`，你需要做以下事情确保你的题解可以被通过：
 
-*Example 1:*
+* 更改数组 `nums` ，使 `nums` 的前 `k` 个元素包含唯一元素，并按照它们最初在 `nums` 中出现的顺序排列。`nums` 的其余元素与 `nums` 的大小不重要。
+* 返回 `k` 。
 
-[subs="verbatim,quotes,macros"]
-----
-Given _nums_ = *[1,1,2]*,
+*判题标准:*
 
-Your function should return length = *`2`*, with the first two elements of _`nums`_ being *`1`* and *`2`* respectively.
+系统会用下面的代码来测试你的题解:
 
-It doesn't matter what you leave beyond the returned length.
-----
+....
+int[] nums = [...]; // 输入数组
+int[] expectedNums = [...]; // 长度正确的期望答案
 
-*Example 2:*
+int k = removeDuplicates(nums); // 调用
 
-[subs="verbatim,quotes,macros"]
-----
-Given _nums_ = *[0,0,1,1,1,2,2,3,3,4]*,
+assert k == expectedNums.length;
+for (int i = 0; i < k; i++) {
+    assert nums[i] == expectedNums[i];
+}
+....
 
-Your function should return length = *`5`*, with the first five elements of _`nums`_ being modified to *`0`*, *`1`*, *`2`*, *`3`*, and *`4`* respectively.
+如果所有断言都通过，那么您的题解将被 *通过*。
 
-It doesn't matter what values are set beyond the returned length.
+*示例 1：*
 
-----
+....
+输入：nums = [1,1,2]
+输出：2, nums = [1,2,_]
+解释：函数应该返回新的长度 2 ，并且原数组 nums 的前两个元素被修改为 1, 2 。不需要考虑数组中超出新长度后面的元素。
+....
 
-*Clarification:*
+*示例 2：*
 
-Confused why the returned value is an integer but your answer is an array?
+....
+输入：nums = [0,0,1,1,1,2,2,3,3,4]
+输出：5, nums = [0,1,2,3,4]
+解释：函数应该返回新的长度 5 ， 并且原数组 nums 的前五个元素被修改为 0, 1, 2, 3, 4 。不需要考虑数组中超出新长度后面的元素。
+....
 
-Note that the input array is passed in by *reference*, which means modification to the input array will be known to the caller as well.
 
-Internally you can think of this:
+*提示：*
 
-[subs="verbatim,quotes,macros"]
-----
-// *nums* is passed in by reference. (i.e., without making a copy)
-int len = removeDuplicates(nums);
+* `1 \<= nums.length \<= 3 * 10^4^`
+* `-10^4^ \<= nums[i] \<= 10^4^`
+* `nums` 已按 *非严格递增* 排列
 
-// any modification to *nums* in your function would be known by the caller.
-// using the length returned by your function, it prints the first *len* elements.
-for (int i = 0; i < len; i++) {
-    print(nums[i]);
-}
-----
 
-== 解题分析
+== 思路分析
+
+双指针：把后面的数据向前拷贝。
 
-把后面的数据向前拷贝。
+image::images/0026-10.png[{image_attr}]
 
 [[src-0026]]
+[tabs]
+====
+一刷::
++
+--
 [{java_src_attr}]
 ----
 include::{sourcedir}/_0026_RemoveDuplicatesFromSortedArray.java[tag=answer]
 ----
+--
 
+二刷::
++
+--
 [{java_src_attr}]
 ----
 include::{sourcedir}/_0026_RemoveDuplicatesFromSortedArray_2.java[tag=answer]
 ----
+--
+
+三刷::
++
+--
+[{java_src_attr}]
+----
+include::{sourcedir}/_0026_RemoveDuplicatesFromSortedArray_3.java[tag=answer]
+----
+--
+====
+
 
 == 参考资料
 

docs/images/0026-10.png

@@ -708,11 +708,16 @@ endif::[]
 |{doc_base_url}/0022-generate-parentheses.adoc[题解]
 |✅ 回溯。也可以去掉回溯过程，使用深度优先遍历。
 
-|{counter:codes}
+|{counter:codes2503}
 |{leetcode_base_url}/swap-nodes-in-pairs/[24. 两两交换链表中的节点^]
 |{doc_base_url}/0024-swap-nodes-in-pairs.adoc[题解]
 |✅ 链表。增加虚拟节点，极大简化代码。
 
+|{counter:codes2503}
+|{leetcode_base_url}/remove-duplicates-from-sorted-array/[26. 删除有序数组中的重复项^]
+|{doc_base_url}/0026-remove-duplicates-from-sorted-array.adoc[题解]
+|✅ 双指针
+
 |===
 
 截止目前，本轮练习一共完成 {codes2503} 道题。

logbook/202503.adoc

@@ -61,7 +61,12 @@
  */
 public class _0026_RemoveDuplicatesFromSortedArray {
   // tag::answer[]
-  public static int removeDuplicates(int[] nums) {
+
+  /**
+   * @author D瓜哥 · https://www.diguage.com
+   * @since 2018-07-19 18:34
+   */
+  public int removeDuplicates(int[] nums) {
     if (Objects.isNull(nums) || nums.length == 0) {
       return 0;
     }
@@ -75,7 +80,7 @@ public static int removeDuplicates(int[] nums) {
     return i + 1;
   }
 
-  public static int removeDuplicates1(int[] nums) {
+  public int removeDuplicates1(int[] nums) {
     if (nums == null || nums.length == 0) {
       return 0;
     }
@@ -106,7 +111,7 @@ public static int removeDuplicates1(int[] nums) {
 
   public static void main(String[] args) {
     int[] nums = {1, 2, 2};
-    System.out.println(removeDuplicates(nums));
+    new _0026_RemoveDuplicatesFromSortedArray().removeDuplicates(nums);
     System.out.println(Arrays.toString(nums));
   }
 }

src/main/java/com/diguage/algo/leetcode/_0026_RemoveDuplicatesFromSortedArray.java

@@ -58,7 +58,11 @@
  */
 public class _0026_RemoveDuplicatesFromSortedArray_2 {
   // tag::answer[]
-  public static int removeDuplicates(int[] nums) {
+  /**
+   * @author D瓜哥 · https://www.diguage.com
+   * @since 2024-07-03 14:23:14
+   */
+  public int removeDuplicates(int[] nums) {
     if (nums == null || nums.length == 0) {
       return 0;
     }

src/main/java/com/diguage/algo/leetcode/_0026_RemoveDuplicatesFromSortedArray_2.java

@@ -0,0 +1,25 @@
+package com.diguage.algo.leetcode;
+
+public class _0026_RemoveDuplicatesFromSortedArray_3 {
+  // tag::answer[]
+  /**
+   * @author D瓜哥 · https://www.diguage.com
+   * @since 2025-05-17 20:48:52
+   */
+  public int removeDuplicates(int[] nums) {
+    int slow = 0, fast = 0;
+    while (fast < nums.length) {
+      if (nums[fast] != nums[slow]) {
+        nums[++slow] = nums[fast];
+      }
+      fast++;
+    }
+    return slow + 1;
+  }
+  // end::answer[]
+  public static void main(String[] args) {
+    new _0026_RemoveDuplicatesFromSortedArray_3()
+      .removeDuplicates(new int[]{0, 0, 1, 1, 1, 2, 2, 3, 3, 4});
+  }
+
+}