【LeetCode】27. Remove Element

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

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

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

二刷：先将vector排序，用迭代器遍历，当出现指定元素时就删除。

Runtime: 4
ms

class Solution {
public:
int removeElement(vector<int>& nums, int val) {
int len = nums.size();
if(len==0) return 0;
sort(nums.begin(),nums.end());
int count = 0;
for(vector<int>::iterator it= nums.begin(); it != nums.end(); it++)
{
if((*it)==val)
{
nums.erase(it);
it--;
count++;
}
}
return len - count;
}
};