This post is completed by 1 user

  • 1
Add to List
Beginner

139. Find a Missing Number From a Sequence of Consecutive Numbers | XOR Method

Input:  Array, arrA[] with a miss­ing num­ber and Range

Out­put: miss­ing number

Example:

int A[] = { 1, 2, 7, 6, 3, 4 };
int range = 7;
Output: MIssing No is :5

In our earlier approach " Click Here " we have seen the method where we had calculated the Sum of numbers, but this approach might fail when the number goes beyond the integer range.

XOR method will better solution in that case.

Approach: - Time Complexity -O(N), Space Complexity - O(1)

  • Do the XOR if 1 to n say it A
  • Do the XOR of the given array say its B
  • Do the XOR of A and B will give the missing no

Code:


Output:

MIssing No is :5