银行家算法c语言实现
时间: 2023-10-28 17:57:44 浏览: 139
银行家算法是一种用于避免死锁的资源分配算法。下面是一个简单的银行家算法的C语言实现示例:
```c
#include <stdio.h>
#include <stdbool.h>
#define MAX_PROCESS 10
#define MAX_RESOURCE 10
int available[MAX_RESOURCE];
int max_claim[MAX_PROCESS][MAX_RESOURCE];
int allocated[MAX_PROCESS][MAX_RESOURCE];
int need[MAX_PROCESS][MAX_RESOURCE];
bool finished[MAX_PROCESS];
void input_data(int n, int m) {
printf("Enter the number of resources:\n");
for (int i = 0; i < m; i++) {
scanf("%d", &available[i]);
}
printf("Enter the maximum claim matrix:\n");
for (int i = 0; i < n; i++) {
for (int j = 0; j < m; j++) {
scanf("%d", &max_claim[i][j]);
}
}
printf("Enter the allocated matrix:\n");
for (int i = 0; i < n; i++) {
for (int j = 0; j < m; j++) {
scanf("%d", &allocated[i][j]);
need[i][j] = max_claim[i][j] - allocated[i][j];
}
}
}
bool is_safe_state(int n, int m) {
int work[m];
bool finish[n];
// 初始化工作向量
for (int i = 0; i < m; i++) {
work[i] = available[i];
}
// 初始化进程状态
for (int i = 0; i < n; i++) {
finish[i] = false;
}
int count = 0;
while (count < n) {
bool found = false;
for (int i = 0; i < n; i++) {
if (finish[i]) {
continue;
}
// 检查是否满足进程 i 的需求
bool can_allocate = true;
for (int j = 0; j < m; j++) {
if (need[i][j] > work[j]) {
can_allocate = false;
break;
}
}
if (can_allocate) {
// 分配资源给进程 i
for (int j = 0; j < m; j++) {
work[j] += allocated[i][j];
}
finish[i] = true;
found = true;
count++;
}
}
// 如果没有找到可分配的进程,则不安全
if (!found) {
return false;
}
}
return true;
}
int main() {
int n, m;
printf("Enter the number of processes:\n");
scanf("%d", &n);
printf("Enter the number of resources:\n");
scanf("%d", &m);
input_data(n, m);
if (is_safe_state(n, m)) {
printf("The system is in a safe state.\n");
} else {
printf("The system is in an unsafe state.\n");
}
return 0;
}
```
这个程序实现了银行家算法的基本逻辑。它首先要求用户输入资源的数量、最大需求矩阵和已分配矩阵。然后,它使用银行家算法检测系统是否处于安全状态,并输出相应的结果。
请注意,这只是一个简单的实现示例,可能需要根据具体情况进行修改和优化。另外,输入数据的格式和合法性检查也需要根据实际需求进行完善。
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