def countSort(arr):
    ans = [[] for _ in range(n)]
    for i in range(len(arr) // 2):
        ans[int(arr[i][0])].append("-")
    for i in range(len(arr) // 2, len(arr)):
        ans[int(arr[i][0])].append(arr[i][1])
    print(" ".join(" ".join(i) for i in ans).strip())