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#include <stdio.h>

#define toggle(a, b, c) \
a^(((1<<b)-1)<<c)
int main(void) {
int a=34;
a = toggle(a, 4, 3);
printf("%x", a);
return 0;
}

- aka[1] October 17, 2015 | Flag Reply

public static int Toggle(int number, int start, int count)
{
	if ((start + count) > 31) 
		throw new IndexOutOfRangeException();
	if (count == 0) return number;

	int mask = 1;	
	while (--count > 0)
		mask = (mask << 1) | 1;

	return number ^ (mask << start);
}

- IC October 24, 2015 | Flag Reply

Create a new bit vector with same length. Set bits from start to end point as opposites to the main vector and do an AND for these two. Use the results as the toggled vector

- Abhi October 17, 2015 | Flag Reply

This code snippet appears long as it prints out the original and modified bit streams.

#include <stdio.h>
#include <stdlib.h>
#define BITBYTES 8

int main(void)
{
	int start_bit = 5, num_of_bits = 15, mynum, j;
	int mask = 01, mask1 = 01, new_mask = 0, i = 0;
	
	printf("Enter number you wish to flip bits for:\t");
	scanf("%d",&mynum);
	printf("\n");

	printf("Printing bits in number enetered as input\n");
	for (j = (BITBYTES*sizeof(int)-1); j >= 0; j--) {
		if (mynum & (mask<<j))
			putchar('1'); 
		else 
			putchar('0');
	}
	printf("\n");
	
	printf("Modified mask stream is shown below:\n");
	for (j = start_bit; j < ((num_of_bits - start_bit) + start_bit); j++) 
		new_mask ^= (mask1 << j);
	printf("%d\n",new_mask);
	
	for (j = (BITBYTES*sizeof(int)-1); j >= 0; j--) {
		if ((mynum & (mask << j))^(new_mask & (mask << j)))
			putchar('1'); 
		else 
			putchar('0');
	}
	mynum ^= new_mask;
	printf("\nThe modified number is: %d\n",mynum);
	system("pause");
}

- Anonymous October 25, 2015 | Flag Reply

{{{int toggleBits( int A, int start_bit, int numBits) { int mask; mask = (1<<numBits)-1; // mask containing numBits 1's in lower bits return (A ^ (mask << (start_bit -1)); // shift the mask to the correct position, then XOR } - lo October 29, 2015 | Flag Reply

#include<stdio.h>
int main()
{
	int a[50],start,no_of_pos,i,n;
	printf("enter length of number");
	scanf("%d",&n);
	for(i=0;i<n;i++)
	scanf("%d",&a[i]);
	printf("string is:");
	for(i=0;i<n;i++)
	printf("%d",a[i]);
	printf("enter starting position and length of number u want to toggle");
	scanf("%d%d",&start,&no_of_pos);
	for(i=n-start;i>=n-(start+no_of_pos);i--)
	{
		if(a[i]==1)
		a[i]=0;
		else
		a[i]=1;
	}

	printf("new string is:");
	for(i=0;i<n;i++)
	printf("%d",a[i]);
	return 0;
}

- apoorva December 23, 2015 | Flag Reply

#include<stdio.h>
#include<stdlib.h>
#include<math.h>

int main()
{
    int data, start, number, power, sum=0;
    printf("enter any data");
    scanf("%d", &data);
    printf("you entered is\n");
    convertD2B(data);
    printf("enter the start bit and number of bits");
    scanf("%d %d", &start, &number);
    for(power=start; power<start+number; power++)
    {
        sum=sum+pow(2, power);
    }

    data=data^sum;
    printf("\nthe modified data is \n");
    convertD2B(data);
    return 0;
}

void convertD2B(int n)
{
    int c, k;
    for (c = 31; c >= 0; c--)
  {
    k = n >> c;
    if (k & 1)
      printf("1");
    else
      printf("0");
  }
  printf("\n");
}

- Sandeep Chauhan December 29, 2015 | Flag Reply