Answer:
import java.util.Scanner;
public class ss11{
public static void main (String[]args) {
Scanner keyboard = new Scanner (System.in)
String a1, a2, a3, a4, a5;
int i1, i2, i3, i4, i5;
System.out.println("Enter a four bit binary number:");
a1= keyboard.next();
a2= a1.substring(0,1);
a3= a1.substring(1,2);
a4= a1.substring(2,3);
a5= a1.substring(3,4);
i1 = Integer.parseInt(a2);
i2 = Integer.parseInt(a3);
i3 = Integer.parseInt(a4);
i4 = Integer.parseInt(a5);
i1= i1 * 8;
i2= i1 * 4;
i3= i1 * 2;
i4= i1 * 1;
i5= i1+i2+i3+i4;
System.out.println("The converted decimal number is: +i5);
}
}
Explanation: