FIFO页面置换算法

本文以序列长度20的{ 7,0,1,2,0,3,0,4,2,3,0,3,2,1,2,0,1,7,0,1};以及页面4；为例；

 #include <stdio.h>

 #define InitPysiBlocks 4
 #define MaxPages 20
 int PysicalBlocks[InitPysiBlocks] = { -,-,-,- };
 int PageSequence[MaxPages] = { ,,,,,,,,,,,,,,,,,,,};

 void FIFO(int py[],int pg[])
 {
     int i,q,j,table[InitPysiBlocks][MaxPages];
     char flag,f[MaxPages];
     for (i = ; i < MaxPages; i++)
     {
         q = ;
         while(pg[i] != py[q] && q != InitPysiBlocks)
             q++;
         if(q == InitPysiBlocks)
             flag = '*';
         else
             flag = ' ';
         if(flag == '*')
         {
             for (j = InitPysiBlocks - ; j > ; j--)
                 py[j] = py[j - ];
             py[] = pg[i];
         }
         for (j = ; j < InitPysiBlocks; j++)
             table[j][i] = py[j];
         f[i] = flag;
     }
     printf("输出结果为下表(-1代表为空,*代表有缺页)：\n");
     for(i = ; i < InitPysiBlocks; i++)
     {
         for(j = ; j < MaxPages; j++)
             printf("%3d",table[i][j]);
         printf("\n");
     }
     for(i = ; i < MaxPages; i++)
         printf("%3c",f[i]);
     printf("\n");
 }

 void main()
 {
     FIFO(PysicalBlocks,PageSequence);
 }

结果：