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 doesn't 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.给定一个数组和一个值,删除该值的所有实例并返回新的长度。 不要为另一个数组分配额外的空间,您必须通过修改带有O(1)额外内存的输入数组来实现这一点。 元素的顺序可以被改变。你在新的长度之外留下什么并不重要。
这题和上题类似通过控制数组的双指针来完成:
public static int removeElement(int[] nums, int val) {
if(nums ==null || nums.length<1){
return 0;
}
int index = 0;
for (int i = 0; i < nums.length; i++) {
if(nums[i]!=val){
nums[index] = nums[i];
index++;
}
}
return index;
}