80. Remove Duplicates from Sorted Array II

public int removeDuplicates(int[] nums) {
if(nums == null || nums.length == 0) {
return 0;
}
boolean flag = false;
int index = 1;
for(int i = 1; i < nums.length; i++) {
if(nums[i-1] == nums[i]) {
if(flag == false) {
flag = true;
nums[index++] = nums[i];
}
} else {
nums[index++] = nums[i];
flag = false;
}
}
return index;
}