动态分区分配方式的模拟程序

实验三使用动态分区分配方式的模拟1、实验目的了解动态分区分配方式中使用的数据结构和分配算法，并进一步加深对动态分区存储管理方式及其实现过程的理解2、实验内容用空闲区低端的空间(2)假设初始状态下，可用的内存空间为640KB，并有下列的请求序列：请分别采用首次适应算法和最佳适应算法，对内存块进行分配和回收，要求每次分配和回收后显示出空闲分区链的情况#include<stdio.h>#include<stdlib.h>structnode //空闲分区链结点的定义node*before;node*after;intsize;intaddress;intstate;nodeL;structusenodeusenode*next;intnum;intadd;intsize;*n;voidInit() //空闲分区链的初始化node*p;p=(node*)malloc(sizeof(node));p->before=&L;p->after=NULL;p->size=640;p->address=0;p->state=0;L.after=p;NULL;L.size=0;ext=NULL;n=&U;node*search(inta)node*p=L.after;returnp;elsewhile(p!=NULL&&a>p->size)p=p->after;returnp;elsereturnp;voidrecovery(inta,intb)

//内存回收算法node*c,*s,*r=L.after;node*d=L.after,*e;usenode*k=U.next,*h=&U;while(k!=NULL&&a!=k->num)h=k;k=k->next;ULL)elseh->next=k->next;if(h->next==NULL)n=h; //if(k->add==r->address+r->size)r->size=r->size+k->size;break;elser=r->after; //r=L.after;=NULL)if(k->add+k->size==r->address)r->address=k->add;r->size=r->size+k->size;break;elser=r->after;

//保证空闲链表中没有相邻的空闲空间if(d->after!=NULL)e=d->after;elsebreak;if(d->address+d->size==e->address)d->after=e->after;while(e->after!=NULL)e->after->before=d;d->size=d->size+e->size;free(e);break;elsed=d->after;r==NULL)r=L.after;c=(node*)malloc(sizeof(node));c->size=b;c->address=k->add;L.after==NULL)c->after=L.after;c->before=&L;L.after=c;elser=L.after;=NULL)if(r->address>c->address)c->after=r;c->before=r->before;r->before->after=c;r->before=c;free(k);return;elser=r->after;free(k);voidalloc(inta,intb)//分配内存算法node*p,*q=L.after;usenode*m;p=search(b);return;m=(usenode*)malloc(sizeof(usenode));//生成一个被占用链表的结点,并插入到该链表的尾部m->add=p->address;m->size=b;m->num=a;m->next=n->next;n->next=m;n=m; //保证n始终指向被占用链表的尾部，方便以后新生成结点的插入if(p->size>b)//如果申请空间的大小小于找到空闲空间的大小的处理ize-b;p->address=p->address+b; //如果申请空间的大小等于找到空闲空间的大小的处理p->after!=NULL)voidsort() //对空闲链表进行排序intmax;node*p,*q,*r,*s;nodea;p=L.after;

//让指针q指向链表的最后一个结点q=p;p=p->after;if(L.after->after==NULL)return;elsewhile(p!=q)s=r=p=L.after;max=r->size;while(s!=q->after)if(s->size>max)max=s->size;r=s;s=s->after;elses=s->after;a.size=q->size;a.address=q->address;q->size=r->size;q->address=r->address;r->size=a.size;r->address=a.address;if(q->before->before==&L)return;elseq=q->before;voidPrint()node*p=L.after;usenode*q=U.next;inti=1;printf("\n空闲区域列表:\n"); address size\n");printf("%-10d",i);printf("%-10d",p->address);printf("%d\n",p->size);p=p->after;i++;return;elseprintf("\n已分配区域列表:\n"); address size\n");printf("%-10d",q->num);printf("%-10d",q->add);printf("%d\n",q->size);q=q->next;voidfirstfit()

//首次适应算法inta,b,i;();e(1)););"%d",&i);ch(i)case1:printf(");d",&a);%d",&b);loc(a,b);reak;case2:printf(");d",&a);%d",&b);a,b);reak;case3:printf("\n");return;voidbestfit()inta,b,i;();e(1){printf("\n1申请空间");printf("2释放空间););"%d",&i);ch(i)case1:printf(");d",&a);%d",&b);loc(a,b);rt();reak;case2:printf(");d",&a);%d",&b);a,b);rt(););reak;case3:printf("\n");return;voidmain()inti;););printf("3退出"););"%d",&i);ch(i)case1:firstfit();break;case2:bestfit();break;case3:return;①开始界面②首次适应算法程序代码——C++语言实现 #defineOK1 #defineERROR0//出错typedefintStatus;typedefstructDuLNode//doublelinkedlistStatusalloc(intch)intID,request;if(request<0||request==0)DuLNode*p=block_first->next;if(p->data.state==Free&&p->data.size==request)if(p->data.state==Free&&p->data.size>request) returnOK;StatusBest_fit(intID,intrequest)DuLinkListtemp=(DuLinkList)malloc(sizeof(DuLNode));DuLNode*p=block_first->next;DuLNode*q=NULL;//记录最佳插入位置&&(p->data.size>request||p->data.size==request))}if(p->data.state==Free&&p->data.