Objective: Given a array of integers, in which every elements occurs even number of times except one number which occurs add number of times. Find out that number.

Example:

int[] A = { 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 5, 6, 6, 6, 6, 7, 7 };
Element appearing add number of times: 5

Approach:

we know that A XOR A = 0 so numbers appearing even number of times will be cancelled out and remaining element will the number which is appearing odd number of times.

Code:

Output:

Element appearing add number of times: 5

__________________________________________________ Top Companies Interview Questions..-

If you find anything incorrect or you feel that there is any better approach to solve the above problem, please write comment.
__________________________________________________

Code Does not work for this input : {2, 7, 5, 4, 5, 2, 4, 3, 5, 2, 4, 4, 2, 7, 4, 4};
Returns ‘6’ which is not even in the array.

tutorialhorizon

Because your input has two numbers 3 and 5 which occurs odd number of times. Objective of problem is ” Given a array of integers, in which every elements occurs even number of times except one number which occurs add number of times”