80. Remove Duplicates from Sorted Array II

Follow up for "Remove Duplicates":
What if duplicates are allowed at most twice?

For example,
Given sorted array nums = [1,1,1,2,2,3],

Your function should return length = 5

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    這道題需要在傳入陣列的基礎上改成去重之後的。其實，當前有多少個不重複的元素，那麼下一個不重複的元素直接覆蓋到這個索引位就可以了。

    我的AC程式碼

public class RemoveDuplicatesfromSortedArrayII {

	/**
	 * @param args
	 */
	public static void main(String[] args) {
		int[] a = { 1, 1, 1, 2, 2, 3 };
		System.out.println(removeDuplicates(a));
		int[] b = { 1, 1, 1, 1, 3, 3 };
		System.out.println(removeDuplicates(b));
	}

	public static int removeDuplicates(int[] nums) {
		if (nums.length == 0) {
			return 0;
		}

		int sum = 1, cnt = 1, pre = nums[0];

		for (int i = 1; i < nums.length; i++) {
			if (pre == nums[i]) {
				cnt++;
				if (cnt <= 2) {
					sum++;
					nums[sum - 1] = nums[i];
				}
			} else {
				pre = nums[i];
				cnt = 1;
				sum++;
				nums[sum - 1] = nums[i];
			}
		}
		return sum;
	}
}