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  1. #include <stdio.h>
  2. #include <stdlib.h>
  3. #include <string.h>
  4.  
  5. #define MAX_PROCESS 10  // 最大进程数
  6.  
  7. // 进程状态枚举
  8. typedef enum {
  9.     READY,      // 就绪态
  10.     RUNNING,    // 运行态
  11.     FINISHED    // 完成态
  12. } ProcessState;
  13.  
  14. // 进程控制块 PCB
  15. typedef struct PCB {
  16.     char name[20];          // 进程名
  17.     int priority;           // 优先数（数值越大优先级越高）
  18.     int needTime;           // 需要运行的时间
  19.     int runTime;            // 已运行时间
  20.     ProcessState state;     // 进程状态
  21.     struct PCB *next;       // 指向下一个进程的指针
  22. } PCB;
  23.  
  24. PCB *readyQueue = NULL;     // 就绪队列头指针
  25. PCB *runningProcess = NULL; // 当前运行进程
  26.  
  27. // 创建新进程
  28. PCB* createProcess(char *name, int priority, int needTime) {
  29.     PCB *p = (PCB*)malloc(sizeof(PCB));
  30.     strcpy(p->name, name);
  31.     p->priority = priority;
  32.     p->needTime = needTime;
  33.     p->runTime = 0;
  34.     p->state = READY;
  35.     p->next = NULL;
  36.     return p;
  37. }
  38.  
  39. // 按优先数降序插入就绪队列（优先数高的在前）
  40. void insertByPriority(PCB *newProcess) {
  41.     if (readyQueue == NULL) {
  42.         readyQueue = newProcess;
  43.         return;
  44.     }
  45.  
  46.     // 如果新进程优先级比队首还高
  47.     if (newProcess->priority > readyQueue->priority) {
  48.         newProcess->next = readyQueue;
  49.         readyQueue = newProcess;
  50.         return;
  51.     }
  52.  
  53.     // 找到合适位置插入
  54.     PCB *current = readyQueue;
  55.     while (current->next != NULL && current->next->priority >= newProcess->priority) {
  56.         current = current->next;
  57.     }
  58.     newProcess->next = current->next;
  59.     current->next = newProcess;
  60. }
  61.  
  62. // 从就绪队列取出优先级最高的进程
  63. PCB* getHighestPriority() {
  64.     if (readyQueue == NULL) return NULL;
  65.     PCB *p = readyQueue;
  66.     readyQueue = readyQueue->next;
  67.     p->next = NULL;
  68.     return p;
  69. }
  70.  
  71. // 显示当前所有进程状态
  72. void displayProcesses() {
  73.     printf("\n========== 当前进程状态 ==========\n");
  74.  
  75.     // 显示运行态进程
  76.     if (runningProcess != NULL) {
  77.         printf("[运行态] 进程名: %s | 优先数: %d | 还需时间: %d | 已运行: %d\n",
  78.                runningProcess->name, runningProcess->priority,
  79.                runningProcess->needTime - runningProcess->runTime,
  80.                runningProcess->runTime);
  81.     }
  82.  
  83.     // 显示就绪队列
  84.     printf("\n【就绪队列】\n");
  85.     if (readyQueue == NULL) {
  86.         printf("  (空)\n");
  87.     } else {
  88.         PCB *p = readyQueue;
  89.         int count = 1;
  90.         while (p != NULL) {
  91.             printf("  [%d] 进程名: %s | 优先数: %d | 还需时间: %d | 状态: 就绪\n",
  92.                    count++, p->name, p->priority,
  93.                    p->needTime - p->runTime);
  94.             p = p->next;
  95.         }
  96.     }
  97.     printf("==================================\n");
  98. }
  99.  
  100. // 调度算法（动态优先数：每运行一次优先数-1）
  101. void schedule() {
  102.     int time = 0;
  103.  
  104.     printf("\n********** 开始进程调度 **********\n");
  105.  
  106.     while (readyQueue != NULL || runningProcess != NULL) {
  107.         printf("\n>>> 时间片 %d <<<\n", time++);
  108.  
  109.         // 如果当前没有运行进程，从就绪队列取一个
  110.         if (runningProcess == NULL) {
  111.             runningProcess = getHighestPriority();
  112.             if (runningProcess != NULL) {
  113.                 runningProcess->state = RUNNING;
  114.                 printf("调度进程 [%s] 进入运行态\n", runningProcess->name);
  115.             }
  116.         }
  117.  
  118.         // 运行当前进程一个时间片
  119.         if (runningProcess != NULL) {
  120.             runningProcess->runTime++;
  121.             printf("进程 [%s] 运行中... (已运行: %d/%d)\n", 
  122.                    runningProcess->name, 
  123.                    runningProcess->runTime, 
  124.                    runningProcess->needTime);
  125.  
  126.             // 检查是否完成
  127.             if (runningProcess->runTime >= runningProcess->needTime) {
  128.                 runningProcess->state = FINISHED;
  129.                 printf("✓ 进程 [%s] 运行完成！\n", runningProcess->name);
  130.                 free(runningProcess);
  131.                 runningProcess = NULL;
  132.             } else {
  133.                 // 动态优先数调整：优先数减1
  134.                 runningProcess->priority--;
  135.                 printf("进程 [%s] 优先数降为 %d\n", 
  136.                        runningProcess->name, runningProcess->priority);
  137.  
  138.                 // 时间片用完，放回就绪队列
  139.                 runningProcess->state = READY;
  140.                 PCB *temp = runningProcess;
  141.                 runningProcess = NULL;
  142.                 insertByPriority(temp);
  143.             }
  144.         }
  145.  
  146.         displayProcesses();
  147.     }
  148.  
  149.     printf("\n********** 所有进程调度完成 **********\n");
  150. }
  151.  
  152. int main() {
  153.     int n, i;
  154.     char name[20];
  155.     int priority, needTime;
  156.  
  157.     printf("===== 最高优先数优先调度算法 =====\n");
  158.     printf("请输入进程数量: ");
  159.     scanf("%d", &n);
  160.  
  161.     for (i = 0; i < n; i++) {
  162.         printf("\n--- 输入第 %d 个进程信息 ---\n", i + 1);
  163.         printf("进程名: ");
  164.         scanf("%s", name);
  165.         printf("优先数(数值越大优先级越高): ");
  166.         scanf("%d", &priority);
  167.         printf("需要运行时间: ");
  168.         scanf("%d", &needTime);
  169.  
  170.         PCB *p = createProcess(name, priority, needTime);
  171.         insertByPriority(p);
  172.     }
  173.  
  174.     printf("\n初始就绪队列:");
  175.     displayProcesses();
  176.  
  177.     // 开始调度
  178.     schedule();
  179.  
  180.     return 0;
  181. }
Success #stdin #stdout 0s 5324KB
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===== 最高优先数优先调度算法 =====
请输入进程数量: 
初始就绪队列:
========== 当前进程状态 ==========

【就绪队列】
  (空)
==================================

********** 开始进程调度 **********

********** 所有进程调度完成 **********
https://ideone.com/B21TOO
language:
C (gcc 8.3)
created:
1 day ago
visibility:
public

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