def partition(arr: list, low: int, high: int) -> int:

    pivot = arr[high]

    i = low - 1

    for j in range(low, high):
        if arr[j] < pivot:
            i += 1
            swap(arr, i, j)

    swap(arr, i + 1, high)
    return i + 1

def swap(arr: list, i: int, j: int) -> None:
    arr[i], arr[j] = arr[j], arr[i]

def quick_sort_h(arr: list, low: int, high: int) -> list:
    # copy = arr.copy()

    if low < high:

        pi = partition(arr, low, high)

        quick_sort_h(arr, low, pi - 1)
        quick_sort_h(arr, pi + 1, high)

    # return copy

# def quick_sort(arr: list) -> list:
#     return quick_sort_h(arr, 0, len(arr) - 1)

def main():
    lines: list[str] = []
    test_cases = int(input())
    while (test_cases != 0):
        n = int(input())

        while (n != 0):

            lines.append(input())

            n -= 1

        quick_sort_h(lines, 0, len(lines) - 1)
        for line in lines:
            print(line)

        lines = []

        test_cases -= 1

if __name__ == "__main__":
    main()