leetcode-problemset/leetcode/originData/remove-duplicates-from-sorted-array.json

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            "title": "Remove Duplicates from Sorted Array",
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            "content": "<p>Given an integer array <code>nums</code> sorted in <strong>non-decreasing order</strong>, remove the duplicates <a href=\"https://en.wikipedia.org/wiki/In-place_algorithm\" target=\"_blank\"><strong>in-place</strong></a> such that each unique element appears only <strong>once</strong>. The <strong>relative order</strong> of the elements should be kept the <strong>same</strong>. Then return <em>the number of unique elements in </em><code>nums</code>.</p>\n\n<p>Consider the number of unique elements of <code>nums</code> to be <code>k</code>, to get accepted, you need to do the following things:</p>\n\n<ul>\n\t<li>Change the array <code>nums</code> such that the first <code>k</code> elements of <code>nums</code> contain the unique elements in the order they were present in <code>nums</code> initially. The remaining elements of <code>nums</code> are not important as well as the size of <code>nums</code>.</li>\n\t<li>Return <code>k</code>.</li>\n</ul>\n\n<p><strong>Custom Judge:</strong></p>\n\n<p>The judge will test your solution with the following code:</p>\n\n<pre>\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 &lt; k; i++) {\n    assert nums[i] == expectedNums[i];\n}\n</pre>\n\n<p>If all assertions pass, then your solution will be <strong>accepted</strong>.</p>\n\n<p>&nbsp;</p>\n<p><strong class=\"example\">Example 1:</strong></p>\n\n<pre>\n<strong>Input:</strong> nums = [1,1,2]\n<strong>Output:</strong> 2, nums = [1,2,_]\n<strong>Explanation:</strong> 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</pre>\n\n<p><strong class=\"example\">Example 2:</strong></p>\n\n<pre>\n<strong>Input:</strong> nums = [0,0,1,1,1,2,2,3,3,4]\n<strong>Output:</strong> 5, nums = [0,1,2,3,4,_,_,_,_,_]\n<strong>Explanation:</strong> 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</pre>\n\n<p>&nbsp;</p>\n<p><strong>Constraints:</strong></p>\n\n<ul>\n\t<li><code>1 &lt;= nums.length &lt;= 3 * 10<sup>4</sup></code></li>\n\t<li><code>-100 &lt;= nums[i] &lt;= 100</code></li>\n\t<li><code>nums</code> is sorted in <strong>non-decreasing</strong> order.</li>\n</ul>\n",
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                    "code": "/**\n * @param {number[]} nums\n * @return {number}\n */\nvar removeDuplicates = function(nums) {\n    \n};",
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                    "code": "# @param {Integer[]} nums\n# @return {Integer}\ndef remove_duplicates(nums)\n    \nend",
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                    "code": "impl Solution {\n    pub fn remove_duplicates(nums: &mut Vec<i32>) -> i32 {\n        \n    }\n}",
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                "In this problem, the key point to focus on is the input array being sorted. As far as duplicate elements are concerned, what is their positioning in the array when the given array is sorted? Look at the image above for the answer. If we know the position of one of the elements, do we also know the positioning of all the duplicate elements?\r\n\r\n<br>\r\n<img src=\"https://assets.leetcode.com/uploads/2019/10/20/hint_rem_dup.png\" width=\"500\"/>",
                "We need to modify the array in-place and the size of the final array would potentially be smaller than the size of the input array. So, we ought to use a two-pointer approach here. One, that would keep track of the current element in the original array and another one for just the unique elements.",
                "Essentially, once an element is encountered, you simply need to <b>bypass</b> its duplicates and move on to the next unique element."
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