用C语言如何模拟三个进程的调度?把代码附在下面。
时间: 2024-03-16 09:42:49 浏览: 13
下面是一个使用C语言实现模拟三个进程调度的示例代码:
```c
#include <stdio.h>
#define NUM_PROCESSES 3
struct Process {
int id;
int time;
};
struct Scheduler {
struct Process* processes[NUM_PROCESSES];
int current;
};
void init_processes(struct Process* processes) {
processes[0].id = 1;
processes[0].time = 5;
processes[1].id = 2;
processes[1].time = 2;
processes[2].id = 3;
processes[2].time = 4;
}
void init_scheduler(struct Scheduler* scheduler, struct Process* processes) {
int i;
for (i = 0; i < NUM_PROCESSES; i++) {
scheduler->processes[i] = &processes[i];
}
scheduler->current = 0;
}
void simulate(struct Scheduler* scheduler) {
int time = 0;
while (1) {
struct Process* current_process = scheduler->processes[scheduler->current];
printf("Time: %d, Process: %d\n", time, current_process->id);
current_process->time--;
if (current_process->time == 0) {
int i;
for (i = scheduler->current; i < NUM_PROCESSES - 1; i++) {
scheduler->processes[i] = scheduler->processes[i + 1];
}
NUM_PROCESSES--;
} else {
scheduler->current = (scheduler->current + 1) % NUM_PROCESSES;
}
if (NUM_PROCESSES == 0) {
break;
}
time++;
}
}
int main() {
struct Process processes[NUM_PROCESSES];
struct Scheduler scheduler;
init_processes(processes);
init_scheduler(&scheduler, processes);
simulate(&scheduler);
return 0;
}
```
在上面的代码中,`Process`结构体表示一个进程,有一个唯一的ID和一个执行时间。`Scheduler`结构体表示调度器,包含一个指向进程的指针数组和当前进程的索引。`init_processes`函数初始化进程的ID和执行时间。`init_scheduler`函数将进程数组分别赋值给调度器中的指针数组,并将当前进程的索引设置为0。`simulate`函数模拟了整个调度过程,直到所有进程都执行完毕为止。在每个时间点上,打印当前时间和正在执行的进程的ID。每执行一次,当进程的执行时间为0时,将其从进程列表中删除。如果所有进程都执行完毕,则跳出循环并结束程序。