생성일: 2022년 1월 14일 오후 5:27
# 뮤직비디오(결정 알고리즘)
import sys
sys.stdin = open("input.txt", "rt")
def Count(capacity):
sum = 0
cnt = 1
for x in music:
if sum+x > capacity:
cnt += 1
sum = x
else:
sum += x
return cnt
n, m = map(int, input().split())
music = list(map(int,input().split()))
maxx = max(music)
lt = 1
rt = sum(music)
res = 0
while lt <= rt:
mid = (lt+rt)//2
if mid >= maxx and Count(mid) <= m:
res = mid
rt = mid - 1
else:
lt = mid + 1
print(res)