【操作系统】实验四 主存空间的分配和回收

#include<stdio.h>
#include<conio.h>
#include<string.h>
#define MAX 24
void firstfit(int num);
void bestfit(int num);
void badfit(int num);
struct partition{

char pn[10];
int begin;
int size;
int end;
char status;
};
typedef struct partition PART;

PART Total[MAX] ;
PART userjob ;
PART backups[MAX] ;

void init(){

strcpy(Total[0].pn,"No.1");
Total[0].begin=0;
Total[0].size=100;
Total[0].end=100;
Total[0].status='u';
}

void input(int num){

int i=0;
for(i=0;i<num;i++){
//作业名
printf("作业名:\n");
scanf("%s" ,&Total[i+1].pn);
//开始内存大小
printf("内存大小:\n");
scanf("%d",&Total[i+1].size);
//作业状态
printf("作业状态:\n");
scanf("%s",&Total[i+1].status);
//作业开始大小
Total[i+1].begin=Total[i].end;
printf("开始地址：%d\n",Total[i+1].begin);
//作业结束大小
Total[i+1].end=Total[i+1].begin+Total[i+1].size;
printf("结束地址：%d\n",Total[i+1].end);

}

}

void output(int num){
int i=0;
printf("内存名\t开始\t大小\t结束\t状态\n");
for(i=0;i<num+1;i++)
{

printf("%s \t %d \t %d \t %d \t %c \n" ,Total[i].pn,Total[i].begin,Total[i].size,Total[i].end,Total[i].status);

}

}

void inputjob(){
printf("作业名:\n");
scanf("%s" ,&userjob.pn);
//开始内存大小
printf("内存大小:\n");
scanf("%d",&userjob.size);
//作业状态
userjob.status='u';
//作业开始大小
userjob.begin=0;
//作业结束大小
userjob.end=0;

}

void selecttypr(int select,int num){

switch(select){
case 1 :
printf("1首次适应算法\n");
firstfit(num);
output(num+1);
break;
case 2 :
printf("2循环首次适应算法");

break;
case 3 :
printf("3最佳适应算法\n");
bestfit(num);
output(num+1);
break;
case 4 :
printf("4最坏适应算法");
badfit(num);
output(num+1);
break;
default :
printf("输入错误");
break;

}

}
void firstfit(int num){
int i,sum;
for(i=0;i<=num;i++){
sum=Total[i+1].size;
if(userjob.size>=sum && Total[i+1].status!='u')
{
Total[num+1].size=userjob.size;
Total[num+1].begin=Total[i].end;
Total[num+1].end=Total[i+1].begin;
strcpy(Total[num+1].pn,userjob.pn);
Total[num+1].status=userjob.status ;
break;
}
}
}

void bestfit(int num){
int i,s,sum;
for(i=0;i<=num;i++){

if(userjob.size>=Total[i+1].size && Total[i+1].status!='u')
{
s=i;
sum=Total[i+1].size;
for(i=i+1;i<sum;i++){
if(Total[i].size>userjob.size&&Total[i].size<sum&&Total[i+1].status!='u'){
sum=Total[i].size;
s=i;
}
}
}

}
Total[num+1].size=userjob.size;
Total[num+1].begin=Total[s].end;
Total[num+1].end=Total[s].begin;
strcpy(Total[num+1].pn,userjob.pn);
Total[num+1].status=userjob.status ;

}
void badfit(int num){
int i,s,sum;
for(i=0;i<=num;i++){

if(userjob.size>=Total[i+1].size && Total[i+1].status!='u')
{
s=i;
sum=Total[i+1].size;
for(i=i+1;i<sum;i++){
if(Total[i].size>userjob.size&&Total[i].size>sum&&Total[i+1].status!='u'){
sum=Total[i].size;
s=i;
}
}
}

}
Total[num+1].size=userjob.size;
Total[num+1].begin=Total[s].end;
Total[num+1].end=Total[s].begin;
strcpy(Total[num+1].pn,userjob.pn);
Total[num+1].status=userjob.status ;
}

void cz(int num){
int i,n=0;
char pn[10];
printf("输入：");
scanf("%s",&pn);
for(i=0;i<=num;i++){
if(strcmp(pn,Total[i+1].pn)==0){
n=1;
break;
}
else n=0;
}
if(n==0)
printf("作业不存在。\n");
else
printf("已终止。\n");
}
void main(){
int num;int select;
printf("初始化，设内存的总量为512k\n");
printf("系统从低地址开始分配，占用100k\n");
init();

printf("=================================");
printf("\n\n\n");
printf("作业的个数 \n");
scanf("%d",&num);
input(num);

printf("=================================");
printf("\n\n\n");
output(num);
//cz(num);
printf("=================================");
printf("\n\n\n");
printf("用户输入作业\n");
inputjob();

printf("=================================");
printf("\n\n\n");
printf("用户选择分配算法\n");
printf("\t\t\t 1首次适应算法\n");
printf("\t\t\t 2循环首次适应算法\n");
printf("\t\t\t 3最佳适应算法\n");
printf("\t\t\t 4最坏适应算法\n");
scanf("%d",&select);
selecttypr(select,num);

}