def solve():
    from heapq import heapify, heappop, heappush

    N, M = map(int, input().split())
    T = list(map(int, input().split()))

    H = [(0, i) for i in range(M)]
    heapify(H)

    for t in T:
        w, j = heappop(H)
        heappush(H, (t + w, j))

    return max(t for t, _ in H)

#==================================================
print(solve())