Remove Duplicates from Sorted Array II

Remove Duplicates from Sorted Array II
描述
Follow up for ”Remove Duplicates”: What if duplicates are allowed at most twice?
For example, Given sorted array A = [1,1,1,2,2,3],
Your function should return length = 5, and A is now [1,1,2,2,3]
分析
加一个变量记录一下元素出现的次数即可。这题因为是已经排序的数组，所以一个变量即可解
决。如果是没有排序的数组，则需要引入一个 hashmap 来记录出现次数。

代码

public class solution {

    public static void main(String[] args) {
        
        int[] A= {1,1,1,2,2,3};
        int n = A.length;
        int index=removeDuplicates(A,n);
        int[] B=new int[index];     //定义好数组长度不好改
        for(int i=0;i<index;i++) {
            B[i]=A[i];
            System.out.println(B[i]);
        }

    }
    public static int removeDuplicates(int A[], int n) {
        if (n == 0) return 0;
        int occur = 1;
        int index = 0;
        for (int i = 1; i < n; i++) {
          if (A[index] == A[i]) {
             if (occur < 2) {
                 A[++index] = A[i];
                 occur++;
             }
           } else {
                  A[++index] = A[i];
                  occur = 1;
                 }
        }
    
        return index + 1;
    }
}