BOJ - 2110 - 공유기 설치

import sys

sys.setrecursionlimit(10 ** 9)
answer = 0
def solve(arr, N, C, minimum, maximum):
    if minimum > maximum:
        return
    dist = (maximum + minimum) // 2

    cnt = 1
    target = 0
    for idx in range(N):
        if arr[idx] >= arr[target] + dist:
            cnt += 1
            target = idx
    if cnt >= C:
        global answer
        answer = max(answer, dist)
        solve(arr, N, C, dist + 1, maximum)
    else:
        solve(arr, N, C, minimum, dist - 1)


def solution():
    global answer
    N, C = map(int, sys.stdin.readline().split())
    arr = [int(sys.stdin.readline()) for _ in range(N)]
    arr.sort()

    solve(arr, N, C, 1, (arr[-1] - arr[0]) // (C - 1) + 1)
    print(str(answer))

solution()

https://www.acmicpc.net/problem/2110