2022-03-04：爱吃香蕉的珂珂。

package main

import "fmt"

func main() {
  piles := []int{30, 11, 23, 4, 20}
  H := 5
  ret := minEatingSpeed(piles, H)
  fmt.Println(ret)
}

func minEatingSpeed(piles []int, h int) int {
  L := 1
  R := 0
  for _, pile := range piles {
    if R < pile {
      R = pile
    }
  }
  ans := 0
  M := 0
  for L <= R {
    M = L + ((R - L) >> 1)
    if hours(piles, M) <= h {
      ans = M
      R = M - 1
    } else {
      L = M + 1
    }
  }
  return ans
}

func hours(piles []int, speed int) int {
  ans := 0
  offset := speed - 1
  for _, pile := range piles {
    ans += (pile + offset) / speed
  }
  return ans
}