时间片轮转调度算法

#include <stdio.h>#include <stdlib.h>#include <string.h>#include<windows.h>/*进程控制块数据结构*/typedef struct node{char name[10];/*进程名*/int prio; /*进程优先级*/int round; /*循环轮转法进程每次轮转的时间片*/int cputime; /*进程累计消耗的CUP时间*/int needtime; /*进程到完成还需要的CUP时间*/int count; /*循环轮转法一个时间片内进程运行时间*/char state; /*进程的状态：'R':运行,'W'：等待,'F'：结束*/struct node *next;/*指向下一个进程的链指针*/}PCB;PCB *finish,*ready,*tail,*run;/*指向三个队列的队首的指针，finish为完成队列头指针，ready为就绪队列头指针，tail为就绪队列的队尾指针，run为当前运行进程头指针*/int N;/*定义进程的数目*/void firstin(void); //调度就绪队列的第一个进程投入运行；void print1(char a); //打印表头行信息void print2(char chose,PCB *p); //打印每一行的状态信息void print(char chose); //打印每执行一次算法后所有的进程的状态信息void insert_prio(PCB *q); //在优先数算法中,将尚未完成的PCB按优先数顺序插入到就绪队列中；void prior_init(char chose); //进程优先级法初始化将进程按优先级插入到就绪队列里void priority(char chose); //进程优先级算法总函数void insert_rr(PCB *q); //在轮转法中，将执行了一个时间片单位（为2），但尚未完成的进程的PCB，插到就绪队列的队尾；void roundrun_init(char chose); //循环轮转法初始化将就绪队列保存为FIFO队列void roundrun(char chose); //循环轮转法总算法void main()//主函数{char chose=' ';while((chose!='e')&&(chose!='E')){fflush(stdin);system("cls");/*printf("\t\t\t两种进程调度算法的模拟\n\n");printf("\tP.进程优先级算法模拟\n\n");*/printf("\tR.循环轮转算法模拟\n\n");printf("\tE.退出程序\n\n");printf("\t请输入你的选择：");scanf("%c",&chose);if((chose!='e')&&(chose!='E')){system("cls");/*if((chose=='P')||(chose=='p')){prior_init(chose);priority(chose);system("cls");} *//*else */if((chose=='r')||(chose=='R')){roundrun_init(chose);roundrun(chose);system("cls");}}}printf("\n\t\t谢谢使用！！！\n");}void firstin(void)//调度就绪队列的第一个进程投入运行；{if(ready!=NULL){run=ready;ready=ready->next;run->state='R';run->next=NULL;}else{run=NULL;}}void print1(char a)//打印表头行信息{if(toupper(a)=='P'){printf("name cputime needtime priority state \n");}else{printf("name cputime needtime count round state \n");}}void print2(char chose,PCB *p)//打印每一行的状态信息{if(toupper(chose)=='P'){printf("%s\t%d\t%d\t%d\t %c\n",p->name,p->cputime,p->needtime,p->prio,p->state);}else{printf("%s\t%d\t%d\t%d\t%d\t%c\n",p->name,p->cputime,p->needtime,p->count,p->round,p->sta te);}}void print(char chose)//打印每执行一次算法后所有的进程的状态信息{PCB *p;print1(chose);if(run!=NULL){print2(chose,run);}p=ready;while(p!=NULL){print2(chose,p);p=p->next;}p=finish;while(p!=NULL){print2(chose,p);p=p->next;}}void insert_prio(PCB *q)/*在优先数算法中,将尚未完成的PCB按优先数顺序插入到就绪队列中；*/{PCB *p,*s,*r; /*p,r用来控制就绪队列滚动，S指向插入的队列*/s=q;p=ready;r=p;if(s->prio>ready->prio)// 要插入的进程的优先级大于ready的优先级{s->next=ready;ready=s;}else//要插入的进程的优先级不大于ready的优先级{while(p){if(p->prio>=s->prio){r=p;p=p->next;}elsebreak;} //找到要插入的位置s->next=p;r->next=s;}}/*void prior_init(char chose)/*进程优先级法初始化将进程按优先级插入到就绪队列里{PCB *p;int i,time;char na[10];ready=NULL;finish=NULL;run=NULL;printf("\t\t进程优先级算法模拟全过程\n\n");printf("输入进程的个数N:\n");scanf("%d",&N);for(i=0;i<N;i++){p=(PCB*)malloc(sizeof(PCB));printf("输入第%d个进程名\n",i+1);scanf("%s",na);printf("完成进程需要的时间片数\n");scanf("%d",&time);strcpy(p->name,na);p->cputime=0;p->needtime=time;p->state='W';p->prio=50-time;//设置进程优先值初值if(ready==NULL){ready=p;ready->next=NULL;}else{insert_prio(p);}printf("当前就绪队列的进程的信息\n");print(chose);}printf("%d个进程已按优先级从高到低进到就绪队列中\n",N);printf("按回车键开始模拟优先级算法.....\n");fflush(stdin);getchar();firstin();}*//*void priority(char chose)//进程优先级算法总函数{int i=1;while(run!=NULL){run->cputime+=1;run->needtime-=1;run->prio-=1;if(run->needtime==0)run->next=finish;finish=run;run->state='F';run->prio=0;run=NULL;firstin();}else{if((ready!=NULL)&&(run->prio<ready->prio)){run->state='W';insert_prio(run);run=NULL;firstin();}}printf("第%d次执行优先级算法\n",i++);print(chose);if(run){printf("按回车键继续下一次优先级算法.....\n");}elseprintf("优先级算法模拟过程结束！！\n");fflush(stdin);getchar();}}*/void insert_rr(PCB *q)//在轮转法中，将执行了一个时间片单位（为2），//但尚未完成的进程的PCB，插到就绪队列的队尾；{tail->next=q;tail=q;q->next=NULL;}void roundrun_init(char chose)/*循环轮转法初始化将就绪队列保存为FIFO队列*/{PCB *p;int i,time;char na[10];ready=NULL;finish=NULL;run=NULL;printf("\t\t循环轮转算法模拟全过程\n\n");printf("输入进程的个数N:\n");scanf("%d",&N);for(i=0;i<N;i++){p=(PCB*)malloc(sizeof(PCB));printf("输入第%d个进程名\n",i+1);scanf("%s",na);printf("完成进程需要的时间片数\n");scanf("%d",&time);strcpy(p->name,na);p->cputime=0;p->needtime=time;p->count=0;p->state='W';p->round=2;if(ready!=NULL){insert_rr(p);}else{p->next=ready;ready=p;tail=p;}printf("当前就绪队列的进程的信息\n");print(chose);}printf("%d个进程已按FIFO进到就绪队列中\n",N);printf("按回车键开始模循环轮转算法.....\n");fflush(stdin);getchar();run=ready;ready=ready->next;run->state='R';}void roundrun(char chose)//循环轮转法总算法{int i=1;while(run!=NULL){run->cputime+=1;run->needtime-=1;run->count+=1;if(run->needtime==0){run->next=finish;finish=run;run->state='F';run->prio=0;run=NULL;if(ready!=NULL){firstin();}}else{if(run->count==run->round){run->count=0;if(ready!=NULL){run->state='W';insert_rr(run);firstin();}}}printf("第%d次执行循环轮转算法\n",i++);print(chose);if(run){printf("按回车键继续下一次循环轮转算法.....\n");}elseprintf("循环轮转算法模拟过程结束！！\n");fflush(stdin);getchar();}}。