golang簡單實現銀行家算法

這周課程設計，以爲會很好玩，實驗書發下來，居然只是實現銀行家算法，失望了……用了小半天時間（原諒我上過操作系統居然連銀行家算法是什麼都忘了，只能回去看書重來），用golang簡單實現了銀行家算法，一下是代碼：

package main

import (
    "fmt"
    "log"
    "os"
)

var Available []int    //可以用資源向量
var Max [][]int        //最大需求矩陣
var Allocation [][]int //已分配矩陣
var Need [][]int       //需求矩陣
var Request []int      //請求向量
var Work []int         //工作向量
var Finish []bool      //Finish向量
var pid int            //請求資源進程號
var serial []int       //用於存儲安全序列
var work [][]int

//初始化
func init() {

    //資源數量爲10,5,7

    //資源數量爲10,5,7

}

//銀行家算法
func Bank() {
    for i := 0; i < len(Request); i++ {
        if Request[i] <= Need[pid][i] {
            continue
        } else {
            log.Fatalln("所需資源超過宣佈最大值")
        }
    }

    for i := 0; i < len(Request); i++ {
        if Request[i] <= Available[i] {
            continue
        } else {
            log.Fatalln("尚無足夠資源，需等待")
        }
    }

    for i := 0; i < len(Available); i++ {
        Available[i] = Available[i] - Request[i]
    }

    for i := 0; i < len(Allocation[0]); i++ {
        Allocation[pid][i] = Allocation[pid][i] + Request[i]
    }

    for i := 0; i < len(Need[0]); i++ {
        Need[pid][i] = Need[pid][i] - Request[i]
    }

    if Safe() {
        fmt.Println("完成分配")
    } else {
        fmt.Println("系統處於不安全狀態，等待")
    }

    fmt.Println("Max:", Max)
    fmt.Println("Allocation:", Allocation)
    fmt.Println("Need:", Need)
    fmt.Println("Available:", Available)
    fmt.Println("Work:", work)
    fmt.Println("安全序列：", serial)
}

//安全性檢查
func Safe() bool {
    Work = Available
    for i := 0; i < len(Max); i++ {
        Finish = append(Finish, false)
    }

    temp := 0
step2:
    for i := temp; i < len(Finish); i++ {
        if Finish[i] == false {
            for j := 0; j < len(Work); j++ {
                if Need[i][j] <= Work[j] {
                    if j == len(Work)-1 {
                        serial = append(serial, i)
                        work = append(work, Work)

                        for j := 0; j < len(Work); j++ {
                            Work[j] = Work[j] + Allocation[i][j]
                        }
                        Finish[i] = true
                        if i == len(Finish)-1 {
                            temp = 0
                        } else {
                            temp = i + 1
                        }
                        goto step2
                    }
                } else {
                    break
                }
            }
        } else {
            continue
        }

        if i == len(Finish)-1 {
            return false
        }
    }

    return true
}

func main() {
lable:
    var sel int
    fmt.Println("********************銀行家算法********************")
    fmt.Println()
    fmt.Println("\t1、測試數據一")
    fmt.Println("\t2、測試數據二")
    fmt.Println("\t3、測試數據三")
    fmt.Println("\t4、退出")
    fmt.Println()
    fmt.Println("************************************************")
    fmt.Print("請做出你的選擇：")
    fmt.Scanln(&sel)
    switch sel {
    //資源總數量爲10,5,7
    case 1:
        //測試數據1
        Available = []int{3, 3, 2}
        Max = [][]int{{7, 5, 3}, {3, 2, 2}, {9, 0, 2}, {2, 2, 2}, {4, 3, 3}}
        Allocation = [][]int{{0, 1, 0}, {2, 0, 0}, {3, 0, 2}, {2, 1, 1}, {0, 0, 2}}
        Need = [][]int{{7, 4, 3}, {1, 2, 2}, {6, 0, 0}, {0, 1, 1}, {4, 3, 1}}
        Request = []int{1, 0, 2}
        pid = 1
    case 2:
        //測試數據2
        Available = []int{2, 3, 0}
        Max = [][]int{{7, 5, 3}, {3, 2, 2}, {9, 0, 2}, {2, 2, 2}, {4, 3, 3}}
        Allocation = [][]int{{0, 1, 0}, {3, 0, 2}, {3, 0, 2}, {2, 1, 1}, {0, 0, 2}}
        Need = [][]int{{7, 4, 3}, {0, 2, 0}, {6, 0, 0}, {0, 1, 1}, {4, 3, 1}}
        Request = []int{3, 3, 0}
        pid = 4
    case 3:
        //測試數據3
        Available = []int{2, 3, 0}
        Max = [][]int{{7, 5, 3}, {3, 2, 2}, {9, 0, 2}, {2, 2, 2}, {4, 3, 3}}
        Allocation = [][]int{{0, 1, 0}, {3, 0, 2}, {3, 0, 2}, {2, 1, 1}, {0, 0, 2}}
        Need = [][]int{{7, 4, 3}, {0, 2, 0}, {6, 0, 0}, {0, 1, 1}, {4, 3, 1}}
        Request = []int{0, 2, 0}
        pid = 0
    case 4:
        os.Exit(0)
    default:
        fmt.Println("沒有此選項")
    }

    //執行銀行家算法
    Bank()
    goto lable
}

很簡陋，只測試了三組數據，如果發現bug，望斧正，謝謝！