[leetcode] 【数组】27. Remove Element

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 in place with constant memory.

The order of elements can be changed. It doesn’t matter what you leave beyond the new length.

Example:

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

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

题解

除去数组中的目标元素，返回剩余元素个数m，并且数组前m个元素为除去目标元素后的数组元素。

和去重复的题类似，两个操作：1计数、2元素移动。

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