先进先出页面置换算法.docx

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1、先进先出页面置换算法#include#include#definemax30typedefstruct{      intvisit_number;//要访问的页面号}nu,number[max];int*memoryblock;//主存中有三个主存块，可装三个页面voidinit_memoryblock(intn)//初始化主存块{      inti=1;      memoryblock=(int*)malloc(sizeof(int));//分配空间      for(i=1;i<=n;i++)      {    

2、         memoryblock[i]=-1;//开始时候没有页面进入，初始为-1      }}voidinit_visitpage(numbernum,intn)//n表示要访问的页面的个数{      inti=0;      intj=3;      printf("输入要访问的页面号:");      for(i=1;i<=n;i++)      {             scanf("%d",&num[i].visit_number);      }      printf("");}voidFIFO_page_dispatch(num

3、bernum,intn)//FIFO页面调度算法{      inti,j=3,temp,counter=0;      for(i=1;i<=n;i++)      {             //----------------------------页面在主存中-------------------------------             for(j=3;j>=1;j--)             {                    if(num[i].visit_number==memoryblock[j])//////要访问的页面在主存中

4、                    {                           printf("(%d)页面在主存块中，换出和换进都是%d号页面:",i,memoryblock[j]);                    }                    break;             }                 //-----------------------------------------------------------------------             //---------------

5、-------------页面不在主存中-----------------------------             if(num[i].visit_number!=memoryblock[1]&&num[i].visit_number!=memoryblock[2]&&num[i].visit_number!=memoryblock[3])/////////////[    1    ]                    /*内存中没有要访问的页面，中断*/             {                    if(memorybloc

6、k[1]!=-1&&memoryblock[2]!=-1&&memoryblock[3]!=-1)                    {                           temp=memoryblock[3];                           memoryblock[3]=memoryblock[2];                           memoryblock[2]=memoryblock[1];                           memoryblock[1]=num[i].visi

7、t_number;                           //---------------------------------                           printf("(%d)——页面发生置换:",i);                           printf("换出(%d号)页面—",temp);                           printf("换进(%d)号页面",num[i].visit_number);                           counter++; 

8、