- Given a decimal number (base 10), convert decimal integer to binary number (base 2) using java.
- We will discuss various methods to convert decimal number to binary.
- Convert decimal to binary using Integer class
- Integer.toBinaryString
- Integer.toString
- Iterative program to convert decimal number to binary number.
- Recursive method to convert decimal number to binary number.
Methods to convert decimal integer to binary:
1.) Convert integer to binary using Integer.toBinaryString
private static String toBinaryString(int number) {
return Integer.toBinaryString(number);
}
2.) Convert decimal integer to binary using Integer.toString
private static String toString(int number) {
return Integer.toString(number, 2);
}
3.) Convert decimal to binary using iterative method
private static String iterative(int number) {
StringBuilder builder = new StringBuilder();
while (number > 0) {
builder.append(number % 2);
number /= 2;
}
return builder.reverse().toString();
}
4.) Convert decimal integer to binary – recursive method
private static String recursive(int number) {
StringBuilder builder = new StringBuilder();
if (number > 0) {
String binaryNumber = recursive(number / 2);
int digit = number % 2;
builder.append(binaryNumber + digit);
}
return builder.toString();
}
Complete: program to convert decimal number to binary
package org.learn;
package org.learn;
import java.util.Scanner;
public class DecimalToBinary {
public static void main(String[] args) {
try (Scanner scanner = new Scanner(System.in)) {
System.out.printf("1. Enter decimal number : ");
int number = scanner.nextInt();
String binary = toBinaryString(number);
System.out.printf("2. Binary of (%d) using toBinaryString method = %s\n", number, binary);
binary = toString(number);
System.out.printf("3. Binary of (%d) using toString method = %s\n", number, binary);
binary = iterative(number);
System.out.printf("4. Binary of (%d) using iterative method = %s\n", number, binary);
binary = recursive(number);
System.out.printf("5. Binary of (%d) using recursive method = %s\n", number, binary);
}
}
private static String toBinaryString(int number) {
return Integer.toBinaryString(number);
}
private static String toString(int number) {
return Integer.toString(number, 2);
}
private static String iterative(int number) {
StringBuilder builder = new StringBuilder();
while (number > 0) {
builder.append(number % 2);
number /= 2;
}
return builder.reverse().toString();
}
private static String recursive(int number) {
StringBuilder builder = new StringBuilder();
if (number > 0) {
String binaryNumber = recursive(number / 2);
int digit = number % 2;
builder.append(binaryNumber + digit);
}
return builder.toString();
}
}
Program output – convert decimal integer to binary
1. Enter decimal number : 10
2. Octal of (10) using toOctalString method = 1010
3. Octal of (10) using toString method = 1010
4. Octal of (10) using iterative method = 1010
5. Octal of (10) using recursive method = 1010
1. Enter decimal number : 25
2. Binary of (25) using toBinaryString method = 11001
3. Binary of (25) using toString method = 11001
4. Binary of (25) using iterative method = 11001
5. Binary of (25) using recursive method = 11001
