GeeksforGeeks

write an algorithm finding the no.of one bits from 1 to n,for given any n value.
complexity should be good
example:
1=1
2=10
3=11
4=100
5=101
6=110
.
.
if n=3 then ur answer is 4
if n=6 then ur answer is 9

Interviewer is looking for an algo in O(log n)time complexity

An array A[1...n] contains all the integers from 0 to n except for one number which is missing. In this problem, we cannot access an entire integer in A with a single operation. The elements of A are represented in binary, and the only operation we can use to access them is “fetch the jth bit of A[i]”, which takes constant time. Write code to find the missing integer. Can you do it in O(n) time?

how can we find wather given number is even or odd without using module operator

How to find whether a machine is 32bit or 64 bit? Write code for this

First some definitions for this problem: a) An ASCII character is one byte long and the most significant bit in the byte is always '0'. b) A Kanji character is two bytes long. The only characteristic of a Kanji character is that in its first byte the most significant bit is '1'.
Now you are given an array of a characters (both ASCII and Kanji) and, an index into the array. The index points to the start of some character. Now you need to write a function to do a backspace (i.e. delete th...

Bit palindrome:
Write a function to check if the bit-wise representation of an integer is a palindrome.

eg. 5, 9, etc. are palindromes.

You are given two 32-bit numbers, N and M, and two bit positions, i and j. Write a method to set all bits between i and j in N equal to M (e.g., M becomes a substring of N located at i and starting at j).
EXAMPLE:
Input: N = 10000000000, M = 10101, i = 2, j = 6
Output: N = 10001010100
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Given a byte, write a code to swap every two bits. [Using bit operators] Eg: Input: 10 01 11 01 Output: 01 10 11 10

Tis was asked for my frend in thought works interview..... How to swap two numbers without using a temporary variable, logical and arithmetic operators?

You are given two 32-bit numbers, N and M, and two bit positions, i and j. Write a method to set all bits between i and j in N equal to M (e.g., M becomes a substring of N located at i and starting at j).
EXAMPLE:
Input: N = 10000000000, M = 10101, i = 2, j = 6
Output: N = 10001010100

given a 32-bit integer x. find the smallest integer x0 > x with the same number of ones in binary representation

Example:
x = 76
x0 = 81

two 32bit integers m,n are given.replace all the bits in m from i to j locations with all the bits in n from k to l locations....
eg. m = 110000000000 n = 10101010 i=3 j=5 k=5 l=7
o/p:110000101000

What are the different ways to say, the value of x can be either a 0 or a 1. Apparently the if then else solution has a jump when written out in assembly.

        if (x == 0)
                y = a
        else
                y = b

There is a logical, arithmetic and a datastructure soln to the above problem.

sort an array of 1,0 in log n time

You are given with Binary Representation of a Number.
Using only BitWise operation (No *, / , %) Find if the Number is divisible by 3.
If yes, then return the quotient. else return -1.

how can we reverse a number using bitwise operators?

Consider a number whose binary representation is : 10110010.
To represent it more clearly if represented as pairs of two bits the number would be : 10-11-00-10
After Swappiing the result should be : 01-11-00-01.

Please provide a generic solution which could be valid for a number of any size(1 byte, 2byte, 4 byte)