Question

NO LOOPS, write a program, in Java, that prompts the user for a hexadecimal string of EXACTLY 4 hex digits, no more, no less, converts the hexadecimal value to its decimal value using string, character parsing, and Math methods learned in this chapter, and then prints the original string and its converted decimal value. NOTE: Hex digits may be in UPPER or lower case.

Answer 1

import java.util.Scanner;

public class HexToDec {

public static void main(String[] args) {

Scanner sc = new Scanner(System.in);

System.out.println("Enter String with 4 digits");

String str=sc.nextLine();

while(str.length()<4){

System.out.println("Enter String with 4 digits");

str=sc.nextLine();

}

System.out.println(finDec(str,0,0,str.length()-1));

}

private static double finDec(String str,double sum,int p,int l) {

if(l<0)

return sum;

char c=str.charAt(l);

int n =0;

if(c>='0' && c<='9'){

n=c-48;

}

if(c=='a'||c=='A')

n=10;

if(c=='b'||c=='B')

n=11;

if(c=='c'||c=='C')

n=12;

if(c=='d'||c=='D')

n=13;

if(c=='e'||c=='E')

n=14;

if(c=='f'||c=='F')

n=15;

sum=sum + n *Math.pow(16, p);

return finDec(str, sum, p+1, l-1);

}

}