银行家算法C语言代码

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语言代码示例：

#include <stdio.h>

// 定义最大进程数和资源数
#define MAX_PROCESS 5
#define MAX_RESOURCE 3

// 定义可用资源数量
int available[MAX_RESOURCE] = {10, 5, 7};

// 定义最大需求矩阵
int max[MAX_PROCESS][MAX_RESOURCE] = {
    {7, 5, 3},
    {3, 2, 2},
    {9, 0, 2},
    {2, 2, 2},
    {4, 3, 3}
};

// 定义已分配矩阵
int allocation[MAX_PROCESS][MAX_RESOURCE] = {
    {0, 1, 0},
    {2, 0, 0},
    {3, 0, 2},
    {2, 1, 1},
    {0, 0, 2}
};

// 定义需求矩阵
int need[MAX_PROCESS][MAX_RESOURCE];

// 定义安全序列数组
int safeSequence[MAX_PROCESS];

// 初始化需求矩阵
void initNeedMatrix() {
    for (int i = 0; i < MAX_PROCESS; i++) {
        for (int j = 0; j < MAX_RESOURCE; j++) {
            need[i][j] = max[i][j] - allocation[i][j];
        }
    }
}

// 检查进程是否满足需求
int isProcessSafe(int process) {
    for (int i = 0; i < MAX_RESOURCE; i++) {
        if (need[process][i] > available[i]) {
            return 0;
        }
    }
    return 1;
}

// 执行银行家算法
void runBankersAlgorithm() {
    int finish[MAX_PROCESS] = {0};
    int count = 0;

    while (count < MAX_PROCESS) {
        int found = 0;

        for (int i = 0; i < MAX_PROCESS; i++) {
            if (finish[i] == 0 && isProcessSafe(i)) {
                for (int j = 0; j < MAX_RESOURCE; j++) {
                    available[j] += allocation[i][j];
                }
                safeSequence[count++] = i;
                finish[i] = 1;
                found = 1;
            }
        }

        if (found == 0) {
            printf("系统处于不安全状态，无法找到安全序列。\n");
            return;
        }
    }

    printf("系统处于安全状态，安全序列为：");
    for (int i = 0; i < MAX_PROCESS; i++) {
        printf("%d ", safeSequence[i]);
    }
    printf("\n");
}

int main() {
    initNeedMatrix();
    runBankersAlgorithm();
    return 0;
}