from heapq import heappush, heappop
n, m = map(int, input().split())
q = list(range(m))
for t in map(int, input().split()):
    v = heappop(q)
    i = v & ((1 << 32) - 1)
    sm = v >> 32
    sm += t
    heappush(q, sm << 32 | i)
print(max(q) >> 32)