Categories of Questions

## Array Questions Belzabar

**Smallest Element Repeated Exactly K Times** We are given an array A[] on size n. We have to find the smallest element that is repeated exactly k times in the array. Example Input A[]= {1, 2 ,2 ,5 ,5 ,2 ,5} K=3 Output Smallest element with frequency K is: 2 Approach 1: Brute force Main idea ...

**First non Repeating Element** We are given an array A. We have to find the first non repeating element in the array. Example Input: A[]={2,1,2,1,3,4} Output: First non-repeating element is: 3 Because 1, 2 is not the answer because they are repeating and 4 is not the answer because we have to find the ...

**Pair of Positive Negative Values in an Array** In pair of positive negative values in an array problem we have given an array A of distinct integers, print all the pairs having positive value and negative value of a number that exists in the array. We need to print pairs in order of their occurrences. A pair whose ...

**Heap Sort** Heap sort is a comparison based sorting technique that is based on a Binary Heap data structure. HeapSort is similar to a selection sort where we find the maximum element and then place that element at the end. We repeat this same process for the remaining elements. Given an unsorted ...

## String Questions Belzabar

**Smallest Element Repeated Exactly K Times** We are given an array A[] on size n. We have to find the smallest element that is repeated exactly k times in the array. Example Input A[]= {1, 2 ,2 ,5 ,5 ,2 ,5} K=3 Output Smallest element with frequency K is: 2 Approach 1: Brute force Main idea ...

## Queue Questions Belzabar

**An Interesting Method to generate Binary Numbers from 1 to n** Problem Statement The problem “An Interesting Method to generate Binary Numbers from 1 to n” states that you are given a number n, print all the numbers from 1 to n in binary form. Examples 3 1 10 11 6 1 10 11 100 101 110 Algorithm The generation ...

**Sorting a Queue without Extra Space** In sorting a queue without extra space problem we have given a queue, sort it using standard queue operations without extra space. Examples Input queue = 10 -> 7 -> 2 -> 8 -> 6 Output queue = 2 -> 6 -> 7 -> 8 -> 10 Input queue = ...