Print 'K'th least significant bit of a number
Last Updated :
15 Jul, 2022
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A number N is given. We need to print its 'K'th Least Significant Bit.
Examples :
Input : num = 10, k = 4 Output : 1 Explanation : Binary Representation of 10 is 1010. 4th LSB is 1. Input : num = 16, k = 3 Output : 0 Explanation : Binary Representation of 16 is 10000. 3rd LSB is 0.
We can easily solve this problem by following steps :
- Shift the number '1' (K-1) times left.
- This will yield a number with all unset bits but the 'K'th bit. Now, we'll perform logical AND of the shifted number with given number.
- All bits except the 'K'th bit will yield 0, and 'K'th bit will depend on the number. This is because, 1 AND 1 is 1. 0 AND 1 is 0.
// CPP code to print 'K'th LSB
#include <bits/stdc++.h>
using namespace std;
//Function returns 1 if set, 0 if not
bool LSB(int num, int K)
{
return (num & (1 << (K-1)));
}
//Driver code
int main()
{
int num = 10, K = 4;
//Function call
cout << LSB(num, K);
return 0;
}
// java code to print 'K'th LSB
import java .io.*;
class GFG {
// Function returns 1 if set, 0 if not
static boolean LSB(int num, int K)
{
boolean x = (num & (1 << (K-1))) != 0;
return (x);
}
// Driver code
public static void main(String[] args)
{
int num = 10, K = 4;
//Function call
if(LSB(num, K))
System.out.println("1") ;
else
System.out.println("0");
}
}
// This code is contributed by Anuj_67
# Python code to print 'K'th LSB
# Function returns 1 if set, 0 if not
def LSB(num, K):
return bool(num & (1 << (K - 1) ))
# Driver code
num, k = 10, 4
res = LSB(num, k)
if res :
print(1)
else:
print(0)
#This code is contributed by Sachin Bisht
// C# code to print 'K'th LSB
using System;
class GFG {
// Function returns 1 if set, 0 if not
static bool LSB(int num, int K)
{
bool x = (num & (1 << (K-1))) != 0;
return (x);
}
// Driver code
static void Main()
{
int num = 10, K = 4;
//Function call
if(LSB(num, K))
Console.Write("1") ;
else
Console.Write("0");
}
}
// This code is contributed by Anuj_67
<?php
// PHP code to print 'K'th LSB
// Function returns 1 if set, 0 if not
function LSB($num, $K)
{
return ($num & (1 << ($K - 1)));
}
// Driver code
$num = 10;
$K = 4;
$r = LSB($num, $K);
if($r)
echo '1';
else
echo '0';
// This code is contributed by Ajit
?>
<script>
// Javascript code to print 'K'th LSB
// Function returns 1 if set, 0 if not
function LSB(num, K)
{
let x = (num & (1 << (K-1))) != 0;
return (x);
}
let num = 10, K = 4;
//Function call
if(LSB(num, K))
document.write("1") ;
else
document.write("0");
</script>
Output :
1
Time Complexity: O(1)
Auxiliary Space: O(1)
