Binary Division using Restoring Algorithm > Java Program

Binary Division using Restoring Algorithm > Java Program

Computer Organization and Architecture

import java.util.*;
class RESTORING
{
public static void lshift(int a[],int q[])
{


for(int i=0;i<3;i++)
{
a[i]=a[i+1];
}
a[3]=q[0];
for(int i=0;i<3;i++)
{
q[i]=q[i+1];
}
q[3]=0;
}

public static int[] add(int a[],int m1[])
{
int carry =0;
int sum[]=new int [4];
for(int i=3;i>=0;i–)
{
sum[i]=(a[i]+m1[i]+carry)%2;
carry=(a[i]+m1[i]+carry)/2;
}
return sum;
}

public static int [] comp2(int m1[])
{
int z[]={0,0,0,1};
for(int i=0;i<3;i++)
{
if(m1[i]==0)
m1[i]=1;
else
m1[i]=0;
}
m1=add(m1,z);
return m1;
}

public static void display(int a[],int q[],int m[])
{
for(int i=0;i<4;i++)
{
System.out.print(a[i]);
}
System.out.print(“\t”);
for(int i=0;i<4;i++)
{
System.out.print(q[i]);
}
System.out.print(“\t”);

for(int i=0;i<4;i++)
{
System.out.print(m[i]);
}
System.out.print(“\t”);
}

public static void main(String args[])
{
Scanner sc=new Scanner(System.in);
int a[]={0,0,0,0};
int m[]=new int[4];
int q[]=new int[4];
int count=4;
int m1[]=new int[4];
System.out.println(“ENTER DIVISOR:”);
for(int i=0;i<=3;i++)
{
m[i]=sc.nextInt();
}

System.out.println(“ENTER DIVIDEND:”);
for(int i=0;i<=3;i++)
{
q[i]=sc.nextInt();
}
System.out.println(“A \t Q \t M \toperation”);
display(a,q,m);
System.out.print(“Initial\n”);

for(int i=count;i>0;i–)
{
for(int j=0;j<4;j++)
{
m1[j]=m[j];
}
lshift(a,q);
display(a,q,m);
System.out.print(“shift\n”);
int c[]=new int[4];
c=comp2(m1);
a=add(a,c);
display(a,q,m);
System.out.print(“Subtract\n”);
if(a[0]==1)
{
q[3]=0;
a=add(a,m);
display(a,q,m);
System.out.print(“Restore\n”);
}
else
{
q[3]=1;
display(a,q,m);
System.out.print(“Set Q0=1\n”);
}
}
}
}

/* RESTORING Division program in java OUTPUT:
ENTER DIVISOR:
0
0
1
1
ENTER DIVIDEND:
0
1
1
1
A Q M operation
0000 0111 0011 Initial
0000 1110 0011 shift
1110 1110 0011 Subtract
0001 1110 0011 Restore
0011 1100 0011 shift
0001 1100 0011 Subtract
0001 1101 0011 Set Q0=1
0011 1010 0011 shift
0001 1010 0011 Subtract
0001 1011 0011 Set Q0=1
0011 0110 0011 shift
0001 0110 0011 Subtract
0001 0111 0011 Set Q0=1 
*/