ISRO CS 2018 Question 23

Introduction

ISRO CS 2018 Question 23 is a programming problem that was posed in the ISRO CS 2018 examination. The problem is related to searching for an element in an array and involves implementing a particular algorithm to solve the problem.

Problem Statement

Given an array of integers, design an algorithm to search for an element x in the array. The algorithm should return the index of the first occurrence of x in the array. If x is not present in the array, the algorithm should return -1.

Solution

To solve this problem, we can implement a linear search algorithm. The linear search algorithm is a simple algorithm that checks each element in an array one-by-one until the target element is found or until the end of the array is reached. The algorithm works as follows:

1. Start at the first element of the array.
2. Check if the current element is equal to the target element x.
3. If it is, return the index of the current element.
4. If it is not, move to the next element in the array.
5. Repeat steps 2-4 until the target element is found or until the end of the array is reached.

def linear_search(arr, x):
    """
    Search for an element x in an array arr using linear search.

    Parameters:
    arr (list): The array to search in.
    x (int): The element to search for.

    Returns:
    int: The index of the first occurrence of x in arr. Returns -1 if x is not present in arr.
    """
    for i in range(len(arr)):
        if arr[i] == x:
            return i
    return -1

The above code defines a function linear_search that takes an array arr and an integer x as input and returns the index of the first occurrence of x in arr using the linear search algorithm. The function returns -1 if x is not present in arr.

Conclusion

In conclusion, ISRO CS 2018 Question 23 is a programming problem related to searching for an element in an array. We can solve this problem using the simple linear search algorithm. The implementation of the algorithm is provided above as the linear_search function.