1.1 KB | 1169 chars
"""
[6236: 용돈 관리](https://www.acmicpc.net/problem/6236)
Tier: Silver 2
Category: binary_search, parametric_search
"""
import sys
from math import sqrt, pi, sin, factorial, ceil, floor
from datetime import datetime, timedelta
SYS_INPUT = True
RECURSION_LIMIT = 10 ** 7
SET_RECURSION = False
BLANK = " "
if SET_RECURSION:
sys.setrecursionlimit(RECURSION_LIMIT)
inp = lambda : sys.stdin.readline().rstrip() if SYS_INPUT else input()
mii = lambda : [*map(int,inp().split())]
mfi = lambda : [*map(float,inp().split())]
ii = lambda : int(inp())
fi = lambda : float(inp())
isplit = lambda : inp().split()
p = print
def gcd(a, b): return gcd(b, a % b) if b > 0 else a
def lcm(a, b): return a * b // gcd(a, b)
def solve():
N, K = mii()
price = [ii() for _ in range(N)]
left = max(price)
right = sum(price)
while left < right:
mid = (left + right) // 2
cnt = 1
money = mid
for p in price:
if money < p:
cnt += 1
money = mid
money -= p
if cnt <= K:
right = mid
else:
left = mid + 1
print(left)
if __name__ == "__main__":
tc = 1
for t in range(1, tc+1):
ret = solve()