编写程序实现先进先出fifo调度算法
时间: 2023-09-08 12:04:08 浏览: 57
FIFO(First-In-First-Out)是一种简单的调度算法,它按照作业或进程到达的顺序来安排它们的执行顺序。以下是一个用C语言编写的FIFO调度算法的示例程序:
```
#include <stdio.h>
#include <stdlib.h>
#define MAX_JOBS 100
typedef struct Job {
int job_id;
int arrival_time;
int execution_time;
} Job;
void fifo(Job jobs[], int num_jobs) {
int current_time = 0;
int total_wait_time = 0;
int i;
for (i = 0; i < num_jobs; i++) {
if (jobs[i].arrival_time > current_time) {
current_time = jobs[i].arrival_time;
}
int completion_time = current_time + jobs[i].execution_time;
int wait_time = current_time - jobs[i].arrival_time;
printf("Job %d:\n", jobs[i].job_id);
printf("Arrival time: %d\n", jobs[i].arrival_time);
printf("Execution time: %d\n", jobs[i].execution_time);
printf("Completion time: %d\n", completion_time);
printf("Wait time: %d\n\n", wait_time);
current_time = completion_time;
total_wait_time += wait_time;
}
float average_wait_time = (float) total_wait_time / num_jobs;
printf("Average wait time: %.2f\n", average_wait_time);
}
int main() {
int num_jobs;
Job jobs[MAX_JOBS];
int i;
printf("Enter the number of jobs: ");
scanf("%d", &num_jobs);
for (i = 0; i < num_jobs; i++) {
printf("Enter arrival time and execution time of Job %d: ", i + 1);
scanf("%d %d", &jobs[i].arrival_time, &jobs[i].execution_time);
jobs[i].job_id = i + 1;
}
fifo(jobs, num_jobs);
return 0;
}
```
在此示例程序中,我们首先定义了一个`Job`结构体,用于存储作业的信息,包括作业ID、到达时间和执行时间。然后,我们实现了一个`fifo`函数,该函数接受一组作业以及作业的数量作为输入,并根据FIFO调度算法进行调度。最后,我们在`main`函数中读取输入作业的数量和每个作业的到达时间和执行时间,并调用`fifo`函数来进行调度并输出结果。
希望以上示例能帮助您理解如何编写一个实现FIFO调度算法的程序。