Searching and Sorting · Algorithms · GATE CSE

Consider an array $A=[10,7,8,19,41,35,25,31]$. Suppose the merge sort algorithm is executed on array $A$ to sort it in increasing order. The merge sort algorithm will carry out a total of 7 merge operations.

A merge operation on sorted left array $L$ and sorted right array $R$ is said to be void if the output of the merge operation is the elements of array $L$ followed by the elements of array $R$.

The number of void merge operations among these 7 merge operations is $\_\_\_\_$ . (answer in integer)

$$\text { The pseudocode of a function fun( ) is given below : }$$

 fun(int A[0, .., n-1]) {
    for i = 0 to n-2
        for j=0 to n-i-2
            if (A[]]>A[j + 1])
                then swap A[j] and A[j+1]
}

Let $A[0, \ldots, 29]$ be an array storing 30 distinct integers in descending order. The number of swap operations that will be performed, if the function fun( ) is called with $A[0, \ldots, 29]$ as argument, is _________. (Answer in integer)

Let $A$ be an array containing integer values. The distance of $A$ is defined as the minimum number of elements in $A$ that must be replaced with another integer so that the resulting array is sorted in non-decreasing order. The distance of the array [2, 5, 3, 1, 4, 2, 6] is __________

Consider the following array.

$$\,\,\,\,\,\,\,{\rm I}.\,\,\,\,\,\,\,$$ Quicksort runs in $$\Theta \left( {{n^2}} \right)$$ time
$$\,\,\,\,\,{\rm I}{\rm I}.\,\,\,\,\,\,\,$$ Bubblesort runs in $$\Theta \left( {{n^2}} \right)$$ time
$$\,\,\,{\rm I}{\rm I}{\rm I}.\,\,\,\,\,\,\,$$ Mergesort runs in $$\Theta \left( n \right)$$ time
$$\,\,\,{\rm I}V.\,\,\,\,\,\,\,$$ Insertion sort runs in $$\Theta \left( n \right)$$ time

$$\,\,\,\,\,\,\,\,$$$$〈89, 19, 50, 17, 12, 15, 2, 5, 7, 11, 6, 9, 100〉$$

Give the correct matching for the following pairs:

Group - 1

Group - 2

Consider an array $A$ of integers of size $n$. The indices of $A$ run from 1 to $n$. An algorithm is to be designed to check whether $A$ satisfies the condition given below.

$\forall i, j \in\{1, \ldots, n-1\}$ such that $i>j,(A[i+1]-A[i])>(A[j+1]-A[j])$

Which one of the following gives the worst case time complexity of the fastest algorithm that can be designed for the problem?

An array $A$ of length $n$ with distinct elements is said to be bitonic if there is an index $1=i=n$ such that $A[1 . . i]$ is sorted in the non-decreasing order and $A[i+1 . . n]$ is sorted in the non-increasing order.

Which ONE of the following represents the best possible asymptotic bound for the worstcase number of comparisons by an algorithm that searches for an element in a bitonic array $A$?

int partition(int a[], int n);

int kth_smallest (int a[], int n, int k)
{
    int left_end = partition (a, n);
    if (left_end+1==k) {
        return a[left_end];
    }
    if (left_end+1 > k) {
        return kth_smallest (___________);
    } else {
        return kth_smallest (___________);   
    }
}

Now consider that a value 35 is inserted into this heap. After insertion, the new heap is

A 3-ary max heap is like a binary max heap, but instead of 2 children, nodes have 3 children. A 3-ary heap can be represented by an array as follows: The root is stored in the first location, a[0], nodes in the next level, from left to right, is stored from a[1] to a[3]. The nodes from the second level of the tree from left to right are stored from a[4] location onward. An item x can be inserted into a 3-ary heap containing n items by placing x in the location a[n] and pushing it up the tree to satisfy the heap property.

Which one of the following is a valid sequence of elements in an array representing 3-ary max heap?

A 3-ary max heap is like a binary max heap, but instead of 2 children, nodes have 3 children. A 3-ary heap can be represented by an array as follows: The root is stored in the first location, a[0], nodes in the next level, from left to right, is stored from a[1] to a[3]. The nodes from the second level of the tree from left to right are stored from a[4] location onward. An item x can be inserted into a 3-ary heap containing n items by placing x in the location a[n] and pushing it up the tree to satisfy the heap property.

Suppose the elements 7, 2, 10 and 4 are inserted, in that order, into the valid 3- ary max heap found in the previous question. Which one of the following is the sequence of items in the array representing the resultant heap?

List - I

List - II

89, 19, 40, 17, 12, 10, 2, 5, 7, 11, 6, 9, 70

List - I

List - II

List - I

List - II