考研笔记之操作系统（四） - 文件管理

题目：

题解：

func poorPigs(buckets, minutesToDie, minutesToTest int) int {
    if buckets == 1 {
        return 0
    }

    combinations := make([][]int, buckets+1)
    for i := range combinations {
        combinations[i] = make([]int, buckets+1)
    }
    combinations[0][0] = 1

    iterations := minutesToTest / minutesToDie
    f := make([][]int, buckets)
    for i := range f {
        f[i] = make([]int, iterations+1)
    }
    for i := 0; i < buckets; i++ {
        f[i][0] = 1
    }
    for j := 0; j <= iterations; j++ {
        f[0][j] = 1
    }

    for i := 1; i < buckets; i++ {
        combinations[i][0] = 1
        for j := 1; j < i; j++ {
            combinations[i][j] = combinations[i-1][j-1] + combinations[i-1][j]
        }
        combinations[i][i] = 1
        for j := 1; j <= iterations; j++ {
            for k := 0; k <= i; k++ {
                f[i][j] += f[k][j-1] * combinations[i][i-k]
            }
        }
        if f[i][iterations] >= buckets {
            return i
        }
    }
    return 0
}