remove-duplicates-from-sorted-array-ii.py

# -*- coding:utf-8 -*-


# Given a sorted array nums, remove the duplicates in-place such that duplicates appeared at most twice 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 1:
#
#
# Given nums = [1,1,1,2,2,3],
#
# Your function should return length = 5, with the first five elements of nums being 1, 1, 2, 2 and 3 respectively.
#
# It doesn't matter what you leave beyond the returned length.
#
# Example 2:
#
#
# Given nums = [0,0,1,1,1,1,2,3,3],
#
# Your function should return length = 7, with the first seven elements of nums being modified to 0, 0, 1, 1, 2, 3 and 3 respectively.
#
# It doesn't matter what values are set beyond the returned length.
#
#
# Clarification:
#
# Confused why the returned value is an integer but your answer is an array?
#
# Note that the input array is passed in by reference, which means modification to the input array will be known to the caller as well.
#
# Internally you can think of this:
#
#
# // nums is passed in by reference. (i.e., without making a copy)
# int len = removeDuplicates(nums);
#
# // any modification to nums in your function would be known by the caller.
# // using the length returned by your function, it prints the first len elements.
# for (int i = 0; i < len; i++) {
#     print(nums[i]);
# }
#
#


class Solution(object):
    def removeDuplicates(self, nums):
        """
        :type nums: List[int]
        :rtype: int
        """
        # recode val counts to a dict
        i = 0
        for n in nums:
            if i < 2 or n > nums[i-2]:
                nums[i] = n
                i += 1
        return i