时钟置换算法c语言代码

以下是时钟置换算法的C语言代码示例：

#include <stdio.h>

#define MAX_FRAMES 3

int main() {
    int reference_string[] = {1, 2, 3, 4, 5, 6, 3, 4, 7, 8, 9, 7, 8, 9, 5, 4, 5, 4, 2 1};
    int frames[MAX_FRAMES] = {0};
    int reference_length = sizeof(reference_string) / sizeof(reference_string[0]);
    int faults = 0;
    int pointer = 0;
    int clock_bits[MAX_FRAMES] = {0};

    for (int i = 0; i < reference_length; i++) {
        int page = reference_string[i];
        int found = 0;

        // Check if page is already in frames
        for (int j = 0; j < MAX_FRAMES; j++) {
            if (frames[j] == page) {
                found = 1;
                clock_bits[j] = 1;
                break;
            }
        }

        // If page is not in frames, replace a page using clock algorithm
        if (!found) {
            while (1) {
                if (clock_bits[pointer] == 0) {
                    frames[pointer] = page;
                    clock_bits[pointer] = 1;
                    pointer = (pointer + 1) % MAX_FRAMES;
                    faults++;
                    break;
                } else {
                    clock_bits[pointer] = 0;
                    pointer = (pointer + 1) % MAX_FRAMES;
                }
            }
        }

        // Print current frames
        printf("Frames: ");
        for (int j = 0; j < MAX_FRAMES; j++) {
            printf("%d ", frames[j]);
        }
        printf("\n");
    }

    printf("Total Page Faults: %d\n", faults);

    return 0;
}