Given a sorted array, remove the duplicates in-place such that each element appear only once 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.
Example:
Given nums = [1,1,2],Your function should return length = 2, with the first two elements of nums being 1 and 2 respectively. It doesn't matter what you leave beyond the new length.
关键
- a sorted array
- Do not allocate extra space for another array
- It doesn't matter what you leave beyond the new length
方法一、利用原本数组空间重新“覆盖”一个新数组。
func removeDuplicates(nums []int) int {
j, n := 0, len(nums)
for i := 1; i < n; i++ {
if nums[j] != nums[i] {
j++
nums[j] = nums[i]
}
}
if n == 0 {
return 0
}
return j+1
}