#include<stdio.h>
#include<stdlib.h>

//Algoritma untuk menerima dan mencetak input pertama kali
void accept(int A[][10],int N[][10],int M[10][10],int W[1][10],int *n,int *m){
	int i,j;
	printf("\n Enter total no. of processes : ");
	scanf("%d",n);
	printf("\n Enter total no. of resources : ");
	scanf("%d",m);
	for(i=0;i<*n;i++){
		printf("\n Process %d\n",i+1);
		for(j=0;j<*m;j++){
			printf(" Allocation for resource %d : ",j+1);
			scanf("%d",&A[i][j]);
			printf(" Maximum for resource %d : ",j+1);
			scanf("%d",&M[i][j]);
		}
	}
	printf("\n Available resources : \n");
	for(i=0;i<*m;i++){
		printf(" Resource %d : ",i+1);
		scanf("%d",&W[0][i]);
	}

	for(i=0;i<*n;i++)
		for(j=0;j<*m;j++)
			N[i][j]=M[i][j]-A[i][j];

	printf("\n Allocation Matrix");
	print(A,*n,*m);
	printf("\n Maximum Requirement Matrix");
	print(M,*n,*m);
	printf("\n Need Matrix");
	print(N,*n,*m);

}

//Fungsi untuk mencetak isi array
void print(int x[][10],int n,int m){
        int i,j;
	for(i=0;i<n;i++){
		printf("\n");
		for(j=0;j<m;j++){
			printf("%d\t",x[i][j]);
		}
	}
}

//Banker's Algorithm
int banker(int A[][10],int N[][10],int W[1][10],int n,int m){
	int j,i,a[10];
	j=safety(A,N,W,n,m,a);
	if(j != 0 ){
		printf("\n\n");
		for(i=0;i<n;i++)
		     printf(" P%d  ",(a[i]+1));
		printf("\n A safety sequence has been detected.\n");
		return 1;
	}else{
		printf("\n Deadlock has occured.\n");
		return 0;
	}
}

//Safety algorithm; AV = available matrix
int safety(int A[][10],int N[][10],int AV[1][10],int n,int m,int a[]){
	int i,j,k,x=0;
	int F[10],W[1][10];
	int pflag=0,flag=0;
	for(i=0;i<n;i++)
		F[i]=0;
	for(i=0;i<m;i++)
		W[0][i]=AV[0][i];

	for(k=0;k<n;k++){
		for(i=0;i<n;i++){
			if(F[i] == 0){
				flag=0;
				for(j=0;j<m;j++){
					if( N[i][j] > W[0][j] )
						flag=1;
				}
				if(flag == 0 && F[i] == 0){
					for(j=0;j<m;j++)
						W[0][j]+=A[i][j];
					F[i]=1;
					pflag++;
					a[x++]=i;
				}
			}
		}
		if(pflag == n)
			return 1;
	}
	return 0;
}

//Resource Request algorithm
void res_request(int A[10][10],int N[10][10],int AV[10][10],int pid,int m)
{
	int reqmat[1][10];
	int i;
	printf("\n Enter additional request :- \n");
	for(i=0;i<m;i++){
		printf(" Request for resource %d : ",i+1);
		scanf("%d",&reqmat[0][i]);
	}

	for(i=0;i<m;i++)
		if(reqmat[0][i] > N[pid][i]){
			printf("\n Error encountered.\n");
			exit(0);
                }

	for(i=0;i<m;i++)
		if(reqmat[0][i] > AV[0][i]){
			printf("\n Resources unavailable.\n");
			exit(0);
		}

	for(i=0;i<m;i++){
		AV[0][i]-=reqmat[0][i];
		A[pid][i]+=reqmat[0][i];
		N[pid][i]-=reqmat[0][i];
	}
}

int main(){
        //variabel untuk uji hasil balik (error atau tidaknya) fungsi algoritma banker
	int ret;
	//allocation matrix
        int A[10][10];
        //max matrix
	int M[10][10];
	//need matrix
        int N[10][10];
	//work matrix; available matrix
        int W[1][10];
	//n: banyak proses
        //m: banyak resources
        int n,m,pid,ch;

        printf("\n DEADLOCK AVOIDANCE USING BANKER'S ALGORITHM\n");
	accept(A,N,M,W,&n,&m);
	ret=banker(A,N,W,n,m);

        if(ret !=0 ){
		printf("\n Do you want make an additional request ? (1=Yes|0=No)");
		scanf("%d",&ch);
		if(ch == 1){
			printf("\n Enter process no. : ");
			scanf("%d",&pid);
			res_request(A,N,W,pid-1,m);
			ret=banker(A,N,W,n,m);
			if(ret == 0 )
				exit(0);
		}
	}else
		exit(0);
	return 0;
}