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.
解题思路：
看代码即可
JAVA实现如下：
public int removeElement(int[] nums, int val) {
int result=0;
for(int i =0;i<nums.length;i++)
if(nums[i]!=val)
nums[result++]=nums[i];
return result;
}