BOJ - 6236 - 용돈 관리

import sys

def solution():
    N, M = map(int, sys.stdin.readline().split())
    money = []
    for _ in range(N):
        money.append(int(sys.stdin.readline()))
    left, right = 0, sum(money)
    result = sum(money)

    while left <= right:
        mid = (left + right) // 2
        temp = mid
        flag = False
        cnt = 1
        for i in range(N):
            if mid < money[i]:
                flag = True
                break
            if temp < money[i]:
                temp = mid
                cnt += 1
            temp -= money[i]

        if flag == False:
            if cnt <= M:
                right = mid - 1
                if mid < result:
                    result = mid
            else:
                left = mid + 1
        else:
            left = mid + 1

    print(result)

solution()

https://www.acmicpc.net/problem/6236