countingSort(A, B, N):
    C # サイズK+1の配列

    for i ← 0 to N-1:
        C[A[i]]++

    for i ← 1 to K:
        C[i] ← C[i] + C[i-1]

    for i ← N-1 downto 0:
        C[A[i]]--
        B[C[A[i]]] ← A[i]