Write a program to print Binary representation of a given number.
Source: Microsoft Interview Set-3
Method 1: Iterative
For any number, we can check whether its ‘i’th bit is 0(OFF) or 1(ON) by bitwise ANDing it with “2^i” (2 raise to i).
1) Let us take number 'NUM' and we want to check whether it's 0th bit is ON or OFF
bit = 2 ^ 0 (0th bit)
if NUM & bit >= 1 means 0th bit is ON else 0th bit is OFF
2) Similarly if we want to check whether 5th bit is ON or OFF
bit = 2 ^ 5 (5th bit)
if NUM & bit >= 1 means its 5th bit is ON else 5th bit is OFF.Let us take unsigned integer (32 bit), which consist of 0-31 bits. To print binary representation of unsigned integer, start from 31th bit, check whether 31th bit is ON or OFF, if it is ON print “1” else print “0”. Now check whether 30th bit is ON or OFF, if it is ON print “1” else print “0”, do this for all bits from 31 to 0, finally we will get binary representation of number.
C++
#include <bits/stdc++.h>
using namespace std;
void bin(long n)
{
long i;
cout << "0";
for (i = 1 << 30; i > 0; i = i / 2)
{
if((n & i) != 0)
{
cout << "1";
}
else
{
cout << "0";
}
}
}
int main(void)
{
bin(7);
cout << endl;
bin(4);
}
|
C
#include<stdio.h>
void bin(unsigned n)
{
unsigned i;
for (i = 1 << 31; i > 0; i = i / 2)
(n & i) ? printf("1") : printf("0");
}
int main(void)
{
bin(7);
printf("\n");
bin(4);
}
|
Java
public class GFG
{
static void bin(long n)
{
long i;
System.out.print("0");
for (i = 1 << 30; i > 0; i = i / 2)
{
if((n & i) != 0)
{
System.out.print("1");
}
else
{
System.out.print("0");
}
}
}
public static void main(String[] args)
{
bin(7);
System.out.println();
bin(4);
}
}
|
Python3
def bin(n) :
i = 1 << 31
while(i > 0) :
if((n & i) != 0) :
print("1", end = "")
else :
print("0", end = "")
i = i // 2
bin(7)
print()
bin(4)
|
C#
using System;
public class GFG{
static void bin(long n)
{
long i;
Console.Write("0");
for (i = 1 << 30; i > 0; i = i / 2)
{
if((n & i) != 0)
{
Console.Write("1");
}
else
{
Console.Write("0");
}
}
}
static public void Main (){
bin(7);
Console.WriteLine();
bin(4);
}
}
|
Javascript
<script>
function bin(n)
{
let i;
document.write("0");
for (i = 1 << 30; i > 0; i = Math.floor(i/2))
{
if((n & i) != 0)
{
document.write("1");
}
else
{
document.write("0");
}
}
}
bin(7);
document.write("<br>");
bin(4);
</script>
|
Output00000000000000000000000000000111
00000000000000000000000000000100
Method 2: Recursive
Following is recursive method to print binary representation of ‘NUM’.
step 1) if NUM > 1
a) push NUM on stack
b) recursively call function with 'NUM / 2'
step 2)
a) pop NUM from stack, divide it by 2 and print it's remainder.C++
#include <bits/stdc++.h>
using namespace std;
void bin(unsigned n)
{
if (n > 1)
bin(n / 2);
cout << n % 2;
}
int main(void)
{
bin(7);
cout << endl;
bin(4);
}
|
C
void bin(unsigned n)
{
if (n > 1)
bin(n / 2);
printf("%d", n % 2);
}
int main(void)
{
bin(7);
printf("\n");
bin(4);
}
|
Java
class GFG {
static void bin(int n)
{
if (n > 1)
bin(n / 2);
System.out.print(n % 2);
}
public static void main(String[] args)
{
bin(7);
System.out.println();
bin(4);
}
}
|
Python3
def bin(n):
if n > 1:
bin(n//2)
print(n % 2, end="")
if __name__ == "__main__":
bin(7)
print()
bin(4)
|
C#
using System;
class GFG {
static void bin(int n)
{
if (n > 1)
bin(n / 2);
Console.Write(n % 2);
}
static public void Main()
{
bin(7);
Console.WriteLine();
bin(4);
}
}
|
PHP
<?php
function bin($n)
{
if ($n > 1)
bin($n/2);
echo ($n % 2);
}
bin(7);
echo ("\n");
bin(4);
?>
|
Javascript
<script>
function bin(n)
{
if (n > 1)
bin(parseInt(n / 2, 10));
document.write(n % 2);
}
bin(7);
document.write("</br>");
bin(4);
</script>
|
Method 3: Recursive using bitwise operator
Steps to convert decimal number to its binary representation are given below:
step 1: Check n > 0
step 2: Right shift the number by 1 bit and recursive function call
step 3: Print the bits of number
C++
#include <bits/stdc++.h>
using namespace std;
void bin(unsigned n)
{
if (n > 1)
bin(n >> 1);
printf("%d", n & 1);
}
int main(void)
{
bin(131);
printf("\n");
bin(3);
return 0;
}
|
Java
class GFG {
static void bin(Integer n)
{
if (n > 1)
bin(n >> 1);
System.out.printf("%d", n & 1);
}
public static void main(String[] args)
{
bin(131);
System.out.printf("\n");
bin(3);
}
}
|
Python3
def bin(n):
if (n > 1):
bin(n >> 1)
print(n & 1, end="")
bin(131)
print()
bin(3)
|
C#
using System;
public class GFG {
static void bin(int n)
{
if (n > 1)
bin(n >> 1);
Console.Write(n & 1);
}
public static void Main()
{
bin(131);
Console.WriteLine();
bin(3);
}
}
|
PHP
<?php
function bin($n)
{
if ($n > 1)
bin($n>>1);
echo ($n & 1);
}
bin(131);
echo "\n";
bin(3);
|
Javascript
<script>
function bin(n)
{
if (n > 1)
bin(n >> 1);
document.write(n & 1);
}
bin(131);
document.write("<br>");
bin(3);
</script>
|
Method 4: Using Bitset of C++
We can use the bitset class of C++ to store the binary representation of any number (positive as well as a negative number). It offers us the flexibility to have the number of bits of our desire, like whether we want to have 32-bit binary representation of just an 8-bit representation of a number.
A complete guide to using bitset can be found on this gfg article LINK.
C++
#include <bits/stdc++.h>
using namespace std;
int main()
{
int n = 5, m = -5;
bitset<8> b(n);
bitset<8> b1(m);
cout << "Binary of 5:" << b << endl;
cout << "Binary of -5:" << b1 << endl;
return 0;
}
|
Output:
Binary of 5:00000101
Binary of -5:11111011
Method 5: Inbuilt library of Python
Python3
def binary(num):
return int(bin(num).split('0b')[1])
if __name__ == "__main__" :
x = 10
binary_x = binary(x)
print(binary_x)
|
https://youtu.be/p0Vyq2_Q_uI
Please write comments if you find anything incorrect, or you want to share more information about the topic discussed above.
This article is compiled by Narendra Kangralkar.
Attention reader! Don’t stop learning now. Get hold of all the important DSA concepts with the DSA Self Paced Course at a student-friendly price and become industry ready. To complete your preparation from learning a language to DS Algo and many more, please refer Complete Interview Preparation Course.
In case you wish to attend live classes with experts, please refer DSA Live Classes for Working Professionals and Competitive Programming Live for Students.
