Category: Binary

Find missing number and duplicate elements in an array

Given an limited range array of integers of size n with all its elements between 1 to n with the exception of one element which occur twice and one number which is missing from the list. Find missing number and the duplicate element in linear time and without using any extra memory.   For example, …

Compute Parity of a Number using Lookup Table

In this post, we will see how to compute parity of a number using lookup table. The parity refers to the number of 1’s in a given binary number.   Odd parity (encoded as 1) means there are an odd number of 1’s and even parity (encoded as 0) means that there are an even …

Conditionally negate a value without branching

In this post, we will see how to conditionally negate a value without branching.   The expression ((flag^(flag-1))*n) negate n when the flag is false and the expression ((n^-flag)+flag) negate n when the flag is true.   How does it work?   1. For (flag ^ (flag – 1)) * n if flag = 0, …