Toggle bits in the given range

Given a non-negative number n and two values l and r. The problem is to toggle the bits in the range l to r in the binary representation of n, i.e, to toggle bits from the rightmost lth bit to the rightmost rth bit. A toggle operation flips a bit 0 to 1 and a bit 1 to 0.

Constraint: 1 <= l <= r <= number of bits in the binary representation of n.

Examples:

Input : n = 17, l = 2, r = 3
Output : 23
(17)10 = (10001)2
(23)10 = (10111)2
The bits in the range 2 to 3 in the binary
representation of 17 are toggled.

Input : n = 50, l = 2, r = 5
Output : 44

Recommended: Please try your approach on {IDE} first, before moving on to the solution.

Approach: Following are the steps:

1. Calculate num as = ((1 << r) – 1) ^ ((1 << (l-1)) – 1) or as ((1 <<r)-l). This will produce a number num having r number of bits and bits in the range l to r are the only set bits.
2. Now, perform n = n ^ num. This will toggle the bits in the range l to r in n.

C/C++

 // C++ implementation to toggle bits in // the given range #include using namespace std;    // function to toggle bits in the given range unsigned int toggleBitsFromLToR(unsigned int n,                                 unsigned int l, unsigned int r) {     // calculating a number 'num' having 'r'     // number of bits and bits in the range l     // to r are the only set bits     int num = ((1 << r) - 1) ^ ((1 << (l - 1)) - 1);        // toggle bits in the range l to r in 'n'     // and return the number //Besides this, we can calculate num as: num=(1<

Java

 // Java implementation to toggle bits in // the given range import java.io.*;    class GFG  {     // Function to toggle bits in the given range     static int toggleBitsFromLToR(int n, int l, int r)     {         // calculating a number 'num' having 'r'         // number of bits and bits in the range l         // to r are the only set bits         int num = ((1 << r) - 1) ^ ((1 << (l - 1)) - 1);             // toggle bits in the range l to r in 'n'         // and return the number         //Besides this, we can calculate num as: num=(1<

Python3

 # Python implementation # to toggle bits in # the given range    # function to toggle bits # in the given range def toggleBitsFromLToR(n,l,r):        # calculating a number     # 'num' having 'r'     # number of bits and     # bits in the range l     # to r are the only set bits     num = ((1 << r) - 1) ^ ((1 << (l - 1)) - 1)         # toggle bits in the     # range l to r in 'n'     # Besides this, we can calculate num as: num=(1<

C#

 // C# implementation to toggle bits  // in the given range using System;    namespace Toggle {     public class GFG     {                             // Function to toggle bits in the given range     static int toggleBitsFromLToR(int n, int l, int r)     {         // calculating a number 'num' having 'r'         // number of bits and bits in the range l         // to r are the only set bits         int num = ((1 << r) - 1) ^ ((1 << (l - 1)) - 1);            // toggle bits in the range l to r in 'n'         //Besides this, we can calculate num as: num=(1<

PHP



Output:

44

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