Remove duplicates from a sorted array without extra space

remove_duplicates_from_sorted_array_wthout_extra_space.py

"""
https://scammingthecodinginterview.com
Week 5: Two Pointer
Problem: 1
"""

class Solution(object):

    def solve(self, a):

        start = 0
        current = 1
        n = len(a)

        while current < n:
            if a[current] == a[start]:
                current += 1
            else:
                start += 1
                a[start] = a[current]
                current += 1

        return start + 1


if __name__ == "__main__":
    a = [1, 1, 1, 2, 2, 3]
    ans = Solution().solve(a)
    print(a)
    print(ans)