from typing import List


class SolutionOne:
    def shuffle(self, nums: List[int], n: int) -> List[int]:
        n_a = []
        l = 0
        for i in range(0, len(nums)):
            if i % 2 == 0:
                n_a.append(nums[l])
                l += 1
            else:
                n_a.append(nums[n])
                n += 1
        return n_a


class SolutionTwo:
    def shuffle(self, nums: List[int], n: int) -> List[int]:
        lst = []
        for i in range(n):
            lst += [nums[i]]
            lst += [nums[i + n]]
        return lst


if __name__ == "__main__":
    nums = [2, 5, 1, 3, 4, 7]
    n = 3
    sol = SolutionTwo
    print(nums)
    print(sol().shuffle(nums, n))
    print("-" * 60)
    nums = [1, 2, 3, 4, 4, 3, 2, 1]
    n = 4
    print(nums)
    print(sol().shuffle(nums, n))
    print("-" * 60)
    nums = [1, 1, 2, 2]
    n = 2
    print(nums)
    print(sol().shuffle(nums, n))
    print("-" * 60)
    nums = [1, 2]
    n = 1
    print(nums)
    print(SolutionOne().shuffle(nums, n))
    print("-" * 60)