本文以序列長度20的{ 7,0,1,2,0,3,0,4,2,3,0,3,2,1,2,0,1,7,0,1};以及頁面4；為例；
1 #include <stdio.h>
2
3 #define InitPysiBlocks 4
4 #define MaxPages 20
5 int PysicalBlocks[InitPysiBlocks] = { -1,-1,-1,-1 };
6 int PageSequence[MaxPages] = { 7,0,1,2,0,3,0,4,2,3,0,3,2,1,2,0,1,7,0,1};
7
8 void LRU(int py[],int pg[])
9 {
10 int i,j,k,m,flag[MaxPages],temp[MaxPages][InitPysiBlocks];
11 int max = 0;
12 char f[MaxPages];
13 for(i = 0; i < InitPysiBlocks; i++)
14 {
15 py[i] = pg[i];
16 flag[i] = i;
17 f[i] = '*';
18 for(j = 0; j < InitPysiBlocks; j++)
19 temp[i][j] = py[j];
20 }
21 for(i = InitPysiBlocks; i < MaxPages; i++)
22 {
23 for(j = 0,k = 0; j < InitPysiBlocks; j++)
24 {
25 if(py[j] != pg[i])
26 k++;
27 else
28 flag[j] = i;
29 }
30 if(k == InitPysiBlocks)
31 {
32 f[i] = '*';
33 max = flag[0] < flag[1]?0:1;
34 for(m = 2; m < InitPysiBlocks; m++)
35 if(flag[m] < flag[max])
36 max = m;
37 py[max] = pg[i];
38 flag[max] = i;
39 for(j = 0; j < InitPysiBlocks; j++)
40 temp[i][j] = py[j];
41 }
42 else
43 {
44 f[i] = ' ';
45 for(j = 0; j < InitPysiBlocks; j++)
46 temp[i][j] = py[j];
47 }
48 }
49 printf("輸出結果為下表(-1代表為空,*代表有缺頁)：\n");
50 for(i = 0; i < InitPysiBlocks; i++)
51 {
52 for(j = 0; j < MaxPages; j++)
53 printf("%3d",temp[j][i]);
54 printf("\n");
55 }
56 for(i = 0; i < MaxPages; i++)
57 printf("%3c",f[i]);
58 printf("\n");
59 }
60
61 void main()
62 {
63 LRU(PysicalBlocks,PageSequence);
64 }
測試：
