(一) 进程调度

#include < stdio.h >
#include < string .h >
#include < iostream.h >

const int block_time = 10 ; // 定义时间片的长度为10秒
const int MAXPCB = 100 ; // 定义最大进程数

// 定义进程结构体
typedef struct node{
char name[ 20 ];
int status;
int time;
int privilege;
int finished;
int wait_time;
}pcb;

pcb pcbs[MAXPCB];
int quantity;

// 初始化函数
void initial(){
int i;

for (i = 0 ;i < MAXPCB;i ++ ){
strcpy(pcbs[i].name, "" );
pcbs[i].status = 0 ;
pcbs[i].time = 0 ;
pcbs[i].privilege = 0 ;

pcbs[i].finished = 0 ;
pcbs[i].wait_time = 0 ;
}

quantity = 0 ;
}

// 读数据函数
int readData(){
FILE * fp;
char fname[ 20 ];
int i;

cout << " 请输入进程流文件名: " ;
cin >> fname;
if ((fp = fopen(fname, " r " )) == NULL){
cout << " 错误,文件打不开,请检查文件名 " << endl;
}
else {
while ( ! feof(fp)){
fscanf(fp, " %s %d %d %d " ,pcbs[quantity].name, & pcbs[quantity].status, & pcbs[quantity].time, & pcbs[quantity
].privilege);
quantity ++ ;
}

// 输出所读入的数据
cout << " 输出所读入的数据 " << endl;
cout << " 进程名 进程状态 所需时间 优先数 " << endl;
for (i = 0 ;i < quantity;i ++ ){
cout << " " << pcbs[i].name << " " << pcbs[i].status << " " << pcbs[i].time << " " << pcbs[i].privilege << endl;
}
return ( 1 );
}
return ( 0 );

}

// 重置数据,以供另一个算法使用
void init()
{
int i;

for (i = 0 ;i < MAXPCB;i ++ ){

pcbs[i].finished = 0 ;
pcbs[i].wait_time = 0 ;
}
}

// 先进先出算法
void FIFO()
{
int i,j;
int total;

// 输出FIFO算法执行流
cout << endl << " --------------------------------------------------------------- " << endl;
cout << " FIFO算法执行流: " << endl;
cout << " 进程名 等待时间 " << endl;
for (i = 0 ;i < quantity;i ++ ){
cout << " " << pcbs[i].name << " " << pcbs[i].wait_time << endl;

for (j = i + 1 ;j < quantity;j ++ ){
pcbs[j].wait_time += pcbs[i].time;
}
}
total = 0 ;
for (i = 0 ;i < quantity;i ++ ){
total += pcbs[i].wait_time;
}
cout << " 总等待时间: " << total << " 平均等待时间: " << total / quantity << endl;

}

// 优先数调度算法
void privilege()
{
int i,j,p;
int passed_time = 0 ;
int total;

int queue[MAXPCB];
int current_privilege = 1000 ;

for (i = 0 ;i < quantity;i ++ ){
current_privilege = 1000 ;
for (j = 0 ;j < quantity;j ++ ){
if ((pcbs[j].finished == 0 ) && (pcbs[j].privilege < current_privilege)){
p = j;
current_privilege = pcbs[j].privilege;
}
}
queue[i] = p;
pcbs[p].finished = 1 ;
pcbs[p].wait_time += passed_time;
passed_time += pcbs[p].time;
}

// 输出优先数调度执行流
cout << endl << " --------------------------------------------------------------- " << endl;
cout << " 优先数调度执行流: " << endl;
cout << " 进程名 等待时间 " << endl;
for (i = 0 ;i < quantity;i ++ ){
cout << " " << pcbs[queue[i]].name << " " << pcbs[queue[i]].wait_time << endl;
}

total = 0 ;
for (i = 0 ;i < quantity;i ++ ){
total += pcbs[i].wait_time;
}
cout << " 总等待时间: " << total << " 平均等待时间: " << total / quantity << endl;

}

// 时间片轮转调度算法
void timer()
{
int i,j,number,flag = 1 ;
int passed_time = 0 ;
int max_time = 0 ;
int round = 0 ;

int queue[ 1000 ];
int total = 0 ;

while (flag == 1 ){
flag = 0 ;
number = 0 ;

for (i = 0 ;i < quantity;i ++ ){
if (pcbs[i].finished == 0 ){
number ++ ;
j = i;
}
}

if (number == 1 ){
queue[total] = j;
total ++ ;
pcbs[j].finished = 1 ;
}

if (number > 1 ){

for (i = 0 ;i < quantity;i ++ ){
if (pcbs[i].finished == 0 ){
flag = 1 ;
queue[total] = i;
total ++ ;
if (pcbs[i].time <= block_time * (round + 1 )){
pcbs[i].finished = 1 ;
}
}
}
}
round ++ ;
}

if (queue[total - 1 ] == queue[total - 2 ]){
total -- ;
}

cout << endl << " --------------------------------------------------------------- " << endl;
cout << " 时间片轮转调度执行流: " ;
for (i = 0 ;i < total;i ++ ){
cout << pcbs[queue[i]].name << " " ;
}


}

// 显示版权信息函数
void version()
{
cout << endl << endl;

cout << " ┏━━━━━━━━━━━━━━━━━━━━━━━┓ " << endl;
cout << " ┃　　　　　　 进程调度模拟系统　 　　　　　　　┃ " << endl;
cout << " ┠───────────────────────———————┨ " << endl;
cout << " ┃　 　 (c)All Right Reserved Neo　　　 　 　┃ " << endl;
cout << " ┃　　　　　　sony006@163.com　　 　　　 ┃ " << endl;
cout << " ┃　　　　　version 2004 build 1122　　　　 ┃ " << endl;
cout << " ┗━━━━━━━━━━━━━━━━━━━━━━━┛ " << endl;
cout << endl << endl;
}


// 主函数
void main()
{
int flag;

version();

initial();

flag = readData();

if (flag == 1 ){
FIFO();
init();

privilege();
init();

timer();
}
}