{ "data": { "question": { "questionId": "26", "questionFrontendId": "26", "categoryTitle": "Algorithms", "boundTopicId": 1166, "title": "Remove Duplicates from Sorted Array", "titleSlug": "remove-duplicates-from-sorted-array", "content": "

Given an integer array nums sorted in non-decreasing order, remove the duplicates in-place such that each unique element appears only once. The relative order of the elements should be kept the same. Then return the number of unique elements in nums.

\n\n

Consider the number of unique elements of nums to be k, to get accepted, you need to do the following things:

\n\n\n\n

Custom Judge:

\n\n

The judge will test your solution with the following code:

\n\n
\nint[] nums = [...]; // Input array\nint[] expectedNums = [...]; // The expected answer with correct length\n\nint k = removeDuplicates(nums); // Calls your implementation\n\nassert k == expectedNums.length;\nfor (int i = 0; i < k; i++) {\n    assert nums[i] == expectedNums[i];\n}\n
\n\n

If all assertions pass, then your solution will be accepted.

\n\n

 

\n

Example 1:

\n\n
\nInput: nums = [1,1,2]\nOutput: 2, nums = [1,2,_]\nExplanation: Your function should return k = 2, with the first two elements of nums being 1 and 2 respectively.\nIt does not matter what you leave beyond the returned k (hence they are underscores).\n
\n\n

Example 2:

\n\n
\nInput: nums = [0,0,1,1,1,2,2,3,3,4]\nOutput: 5, nums = [0,1,2,3,4,_,_,_,_,_]\nExplanation: Your function should return k = 5, with the first five elements of nums being 0, 1, 2, 3, and 4 respectively.\nIt does not matter what you leave beyond the returned k (hence they are underscores).\n
\n\n

 

\n

Constraints:

\n\n\n", "translatedTitle": "删除有序数组中的重复项", "translatedContent": "

给你一个 非严格递增排列 的数组 nums ，请你 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。

\n\n

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：

\n\n\n\n

判题标准:

\n\n

系统会用下面的代码来测试你的题解:

\n\n
\nint[] nums = [...]; // 输入数组\nint[] expectedNums = [...]; // 长度正确的期望答案\n\nint k = removeDuplicates(nums); // 调用\n\nassert k == expectedNums.length;\nfor (int i = 0; i < k; i++) {\n    assert nums[i] == expectedNums[i];\n}
\n\n

如果所有断言都通过，那么您的题解将被 通过。

\n\n

 

\n\n

示例 1：

\n\n
\n输入：nums = [1,1,2]\n输出：2, nums = [1,2,_]\n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。\n
\n\n

示例 2：

\n\n
\n输入：nums = [0,0,1,1,1,2,2,3,3,4]\n输出：5, nums = [0,1,2,3,4]\n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。\n
\n\n

 

\n\n

提示：

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