c实现银行家算法的资源分配
时间: 2023-11-18 08:04:46 浏览: 43
以下是C语言实现银行家算法的资源分配的示例代码:
```c
#include <stdio.h>
#include <stdbool.h>
#define MAX_PROCESS 10
#define MAX_RESOURCE 10
int available[MAX_RESOURCE];
int max[MAX_PROCESS][MAX_RESOURCE];
int allocation[MAX_PROCESS][MAX_RESOURCE];
int need[MAX_PROCESS][MAX_RESOURCE];
bool finish[MAX_PROCESS];
int num_process, num_resource;
bool is_safe() {
int work[MAX_RESOURCE];
for (int i = 0; i < num_resource; i++) {
work[i] = available[i];
}
bool finish_copy[MAX_PROCESS];
for (int i = 0; i < num_process; i++) {
finish_copy[i] = finish[i];
}
bool found;
do {
found = false;
for (int i = 0; i < num_process; i++) {
if (!finish_copy[i]) {
bool can_finish = true;
for (int j = 0; j < num_resource; j++) {
if (need[i][j] > work[j]) {
can_finish = false;
break;
}
}
if (can_finish) {
finish_copy[i] = true;
found = true;
for (int j = 0; j < num_resource; j++) {
work[j] += allocation[i][j];
}
}
}
}
} while (found);
for (int i = 0; i < num_process; i++) {
if (!finish_copy[i]) {
return false;
}
}
return true;
}
bool request_resources(int process_id, int request[]) {
for (int i = 0; i < num_resource; i++) {
if (request[i] > need[process_id][i] || request[i] > available[i]) {
return false;
}
}
for (int i = 0; i < num_resource; i++) {
available[i] -= request[i];
allocation[process_id][i] += request[i];
need[process_id][i] -= request[i];
}
if (is_safe()) {
return true;
} else {
for (int i = 0; i < num_resource; i++) {
available[i] += request[i];
allocation[process_id][i] -= request[i];
need[process_id][i] += request[i];
}
return false;
}
}
int main() {
printf("请输入进程数和资源数:");
scanf("%d%d", &num_process, &num_resource);
printf("请输入每种资源的总量:");
for (int i = 0; i < num_resource; i++) {
scanf("%d", &available[i]);
}
printf("请输入每个进程所需的各种资源数量:\n");
for (int i = 0; i < num_process; i++) {
printf("请输入进程 %d 的资源需求量:", i);
for (int j = 0; j < num_resource; j++) {
scanf("%d", &max[i][j]);
need[i][j] = max[i][j];
}
}
printf("请输入每个进程已经分配的各种资源数量:\n");
for (int i = 0; i < num_process; i++) {
printf("请输入进程 %d 的资源分配量:", i);
for (int j = 0; j < num_resource; j++) {
scanf("%d", &allocation[i][j]);
need[i][j] -= allocation[i][j];
}
}
for (int i = 0; i < num_process; i++) {
finish[i] = false;
}
if (is_safe()) {
printf("当前状态是安全的。\n");
} else {
printf("当前状态是不安全的。\n");
}
int process_id;
int request[MAX_RESOURCE];
printf("请输入请求资源的进程编号:");
scanf("%d", &process_id);
printf("请输入请求的各种资源数量:");
for (int i = 0; i < num_resource; i++) {
scanf("%d", &request[i]);
}
if (request_resources(process_id, request)) {
printf("请求成功,当前状态是安全的。\n");
} else {
printf("请求失败,当前状态是不安全的。\n");
}
return 0;
}
```