﻿ Java exercises: Convert a binary number to hexadecimal number - w3resource # Java Exercises: Convert a binary number to hexadecimal number

## Java Basic: Exercise-23 with Solution

Write a Java program to convert a binary number to hexadecimal number.

Binary number: A binary number is a number expressed in the base-2 numeral system or binary numeral system. This system uses only two symbols: typically 0(zero) and 1(one).

Hexadecimal number: This is a positional numeral system with a radix, or base, of 16. Hexadecimal uses sixteen distinct symbols, most often the symbols 0-9 to represent values zero to nine, and A, B, C, D, E, F (or alternatively a, b, c, d, e, f) to represent values ten to fifteen.

Test Data:
Input a binary number: 1101

Pictorial Presentation: Binary to Hexadecimal number Sample Solution:

Java Code:

``````import java.util.Scanner;
public class Exercise23 {
public static void main(String[] args)
{
int[] hex = new int;
int i = 1, j = 0, rem, dec = 0, bin;
Scanner in = new Scanner(System.in);
System.out.print("Input a Binary Number: ");
bin = in.nextInt();
while (bin > 0) {
rem = bin % 2;
dec = dec + rem * i;
i = i * 2;
bin = bin / 10;
}
i = 0;
while (dec != 0) {
hex[i] = dec % 16;
dec = dec / 16;
i++;
}
for (j = i - 1; j >= 0; j--)
{
if (hex[j] > 9)
{
System.out.print((char)(hex[j] + 55)+"\n");
} else
{
System.out.print(hex[j]+"\n");
}
}
}
}
```
```

Sample Output:

```Input a Binary Number: 1101
```

Flowchart: Java Code Editor:

What is the difficulty level of this exercise?

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## Java: Tips of the Day

Execution of console commands:

Java allows you to execute console commands directly from code using a class Runtime. It is very important not to forget about exception handling.

For example, let's try to open a PDF file through a Java terminal:

```import java.io.BufferedReader;
import java.io.InputStream;

public class ShellCommandExec {

public static void main(String[] args) {
String gnomeOpenCommand = "gnome-open //home//user//Documents//MyDoc.pdf";

try {
Runtime rt = Runtime.getRuntime();
Process processObj = rt.exec(gnomeOpenCommand);

InputStream stdin = processObj.getErrorStream();

String myoutput = "";