Banker’s Algorithm

bankers.c

#include <stdio.h>
#define MAX 20

typedef struct {
    int id;
    int done;
    int claims[MAX];
    int allocations[MAX];
    int needs[MAX];
} Process;

int main() {
    int np,nr,flag;
    Process ps[MAX];
    int Resources[MAX];
    int Available[MAX];
    int safe_sequence[MAX];
    printf("Number of processes?\n");
    scanf("%d",&np);
    printf("Number of Resources?\n");
    scanf("%d",&nr);
    printf("Claim Matrix:\n");
    for (int i = 0; i < np; i++) {
        ps[i].id = i+1;
        ps[i].done = 0;
        for (int j = 0; j < nr; j++) {
            scanf("%d",&ps[i].claims[j]);
        }
    }
    printf("Allocation Matrix:\n");
    for (int i = 0; i < np; i++) {
        for (int j = 0; j < nr; j++) {
            scanf("%d",&ps[i].allocations[j]);
            ps[i].needs[j] = ps[i].claims[j] - ps[i].allocations[j];
        }
    }
    printf("Resource Vector:\n");
    for (int i = 0; i < nr; i++) scanf("%d",&Resources[i]);
    for (int i = 0; i < nr; i++) {
        Available[i] = 0;
        for (int j = 0; j < np; j++) Available[i] += ps[j].allocations[i];
        Available[i] = Resources[i] - Available[i];
    }

    printf("\nNeed Matrix:\n");
    printf("   ");
    for (int j = 0; j < nr; j++) printf("R%d ",j+1);
    printf("\n");
    for (int i = 0; i < np; i++) {
        printf("P%d ",i+1);
        for (int j = 0; j < nr; j++) printf("%2d ",ps[i].needs[j]);
        printf("\n");
    }

    printf("\nResource Vector: ");
    for (int j = 0; j < nr; j++) printf("%d ",Resources[j]);
    printf("\n");
    
    printf("Available Vector: ");
    for (int j = 0; j < nr; j++) printf("%d ",Available[j]);
    printf("\n");

    for (int i = 0; i < np; i++) {
        for (int j = 0; j < np; j++) {
            if (ps[j].done) continue;
            flag = 1;
            for (int k = 0; k < nr; k++) {
                if (ps[j].needs[k] > Available[k]) {
                    flag = 0;
                    break;
                }
            }
            if (flag) {
                for (int k = 0; k < nr; k++) {
                    Available[k] += ps[j].allocations[k];
                    ps[j].needs[k] = 0;
                    safe_sequence[i] = ps[j].id;
                }
                ps[j].done = 1;
                break;
            }
        }
    }
    printf("\nClaim Matrix:\n");
    printf("   ");
    for (int j = 0; j < nr; j++) printf("R%d ",j+1);
    printf("\n");
    for (int i = 0; i < np; i++) {
        printf("P%d ",i+1);
        for (int j = 0; j < nr; j++) printf("%2d ",ps[i].claims[j]);
        printf("\n");
    }
    printf("\nAllocation Matrix:\n");
    printf("   ");
    for (int j = 0; j < nr; j++) printf("R%d ",j+1);
    printf("\n");
    for (int i = 0; i < np; i++) {
        printf("P%d ",i+1);
        for (int j = 0; j < nr; j++) printf("%2d ",ps[i].allocations[j]);
        printf("\n");
    }
    printf("\nSafe Sequence: ");
    for (int i = 0; i < np; i++) printf("P%d ",safe_sequence[i]);
    printf("\n");
    return 0;
}

example.md