class Solution {
public:
int removeElement(vector<int>& nums, int val)
{
if(nums.empty())
return 0;
const int n=nums.size();
int count=0;
for(int i=0;i<n;++i)
{
if(nums[i]==val)
++count;
else
nums[i-count]=nums[i];
}
return n-count;
}
};
例如: 1,2,3,4,5,6,4,7,8 val=4
1,2,3,4,count=1,前移-> 1,2,3,5,6,6,4,count=2,前移-> 1,2,3,5,6,7,8,7,8