Leetcodes Solution 27 Remove Element

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Given an array and a value, remove all instances of that value in-place and return the new length.

Do not allocate extra space for another array, you must do this by modifying the input array in-place with O(1) extra memory.

The order of elements can be changed. It doesnt matter what you leave beyond the new length.

Example:

Given nums = [3,2,2,3], val = 3,

Your function should return length = 2, with the first two elements of nums being 2.

思路1

把不等於給定val的元素放在vector前端就可以了

class Solution {public: int removeElement(vector<int>& nums, int val){ int n = nums.size(); int begin = 0; for(int i = 0; i < n; i++) if(nums[i] != val) nums[begin++] = nums[i]; return begin; }};

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