#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h> //bool类型数据头函数
#include <iostream>
using namespace std;
#define processNum 5 //五个进程
#define resourceNum 3 //三类资源
//初始状态
int p;
//work表示系统中的可用资源
int work[resourceNum];
//请求的各类资源
int Request[resourceNum];
//判断各类资源是否用完
bool Finish[processNum];
int Available[resourceNum]={3,3,2};//可利用资源
//最大的需求量
int Max[processNum][resourceNum]={7,5,3,3,2,2,9,0,2,2,2,2,4,3,3};
//还需要多少对各类资源的需求
int Need[processNum][resourceNum]={7,4,3,1,2,2,6,0,0,0,1,1,4,3,1};
//分配矩阵
int Allocation[processNum][3]={0,1,0,2,0,0,3,0,2,2,1,1,0,0,2};
//输出初始化的信息表
void print1()
{int i,j;printf("系统剩余资源数:");for(j = 0;j < resourceNum;j++)printf("%d ",Available[j]);printf("\n");printf("============当前资源分配状态=========\n");printf("process=== Max =====Allocation=====  Need\n");for(i = 0;i < processNum;i++){printf("p%d        ",i);for(j = 0;j < resourceNum;j++)printf("%d ",Max[i][j]);//输出进程需要的最大需求量 printf("       ");for(j = 0;j < resourceNum;j++)printf("%d ",Allocation[i][j]);//输出进程的各类资源的分配 printf("       ");for(j = 0;j < resourceNum;j++)printf("%d ",Need[i][j]);//输出各类资源仍需要的资源数目 printf("       \n");}
}
void print2(int i)
{int j;if(Need[i][0]==0&&Need[i][1]==0&&Need[i][2]==0){for(int te=0;te<resourceNum;te++){work[te]+=Allocation[i][te];Available[te]+=Allocation[i][te];}}printf("p%d        ",i);for(j = 0;j < resourceNum;j++)printf("%d ",work[j]);printf("       ");for(j = 0;j < resourceNum;j++)printf("%d ",Need[i][j]);printf("       ");for(j = 0;j < resourceNum;j++)printf("%d ",Allocation[i][j]);printf("       ");for(j = 0;j < resourceNum;j++)printf("%d ",work[j]);printf("       ");for(j = 0;j < resourceNum;j++)if(!Finish[i])break;if(j == resourceNum)printf("true");elseprintf("false");printf("       \n");
}
//进程不安全，回收预分配的资源
void recycle()
{int j;for(j = 0;j < resourceNum;j++){Need[p][j] += Request[j];Available[j] += Request[j];Allocation[p][j] -= Request[j];}printf("系统进程资源状态不改变！\n");
}
//检测分配是否安全。
void Test_safety()
{int i,j,te;int finish = 0,Done = 0; //Done一轮遍历下完成的，finish总共完成的int safeseries[processNum] = {-1,-1,-1,-1,-1};//初始化for(i = 0;i < processNum;i++)Finish[i] = false;for(j = 0;j < resourceNum;j++)work[j] = Available[j]; //初始值等于Available;// 查找未完成进程，且当前进程尚需资源不大于系统剩余资源;i = 0;while(finish != processNum){j = 0;if(Finish[i] == false)//如果这个进程的还需要的各类资源还大于系统当前的资源的，break; {for(j = 0;j < resourceNum;j++)if(Need[i][j] > work[j]) break;}if(j == resourceNum){//此时代表当前的系统资源可以满足这个进程//那么可以对这个进程的资源进程回收。 Finish[i] = true;//代表该进程已经被完成。 print2(i);safeseries[finish++] = i; //记录下安全序列for(j = 0;j < resourceNum;j++)//开始资源的回收 work[j] += Allocation[i][j];}i++; //下一个进程//一轮遍历后，判断是否还有可分配进程if(i >= processNum){i = i % processNum;if(Done == finish) //判断本轮完成进程是否等于上一轮，是则代表没有可执行进程break;else Done = finish; //否则将本轮完成进程数赋值给Done}}if(finish == processNum){printf("进程P%d请求通过,此时安全序列为：",p);for(i = 0;i < processNum;i++)printf("p%d ",safeseries[i]);printf("\n");print1(); //打印出此刻系统资源分配状态}else{recycle();printf("进程死锁，进程P%d请求无法通过!\n",p);print1();}
}
void judge_assign()
{int j;for(j = 0;j < resourceNum;j++){//当前请求资源加上已分配资源不能大于最大需求资源；if(Request[j] + Allocation[p][j] > Max[p][j]){printf("当前请求资源+已分配资源>最大需求资源:无法满足!错误!\n");break;}//当前请求资源不能大于系统现有资源；if(Request[j] > Available[j]){printf("当前请求资源>系统现有资源:无法满足!错误!\n");break;}}if(j == resourceNum){//尝试分配资源for(j = 0;j < resourceNum;j++){Need[p][j] -= Request[j];Available[j] -= Request[j];Allocation[p][j] += Request[j];}//检查此时系统的安全性printf("===========安全序列===========\n");printf("process=== Work===== Need =====Allocation=====work+allocation==finish\n");Test_safety();}
}
int main()
{int i;print1();printf("===========此时安全序列===========\n");printf("process=== Work===== Need =====Allocation=====work+allocation==finish\n");Test_safety();while(1){printf("存在进程0,1,2,3,4,资源类别0,1,2\n请依次输入请求资源的进程和进程请求的A,B,C类资源数\n例如：1 0 0 1 \n");scanf("%d",&p);for(i = 0;i < resourceNum;i++)scanf("%d",&Request[i]);//尝试分配资源给进程judge_assign();}return 0;
}