linear_search.cpp File Reference

Linear search algorithm More...

#include <iostream>
#include <cassert>

Include dependency graph for linear_search.cpp:

Functions
int	LinearSearch (int *array, int size, int key)
	for assert More...
static void	tests ()
	Self-test implementations. More...
int	main ()
	Main function. More...

Detailed Description

Linear search algorithm

Author

Unknown author

Ritika Mukherjee

Function Documentation

LinearSearch()

int LinearSearch	(	int *	array,
		int	size,
		int	key
	)

for assert

for IO operations

[Algorithm implementation for linear search]

Parameters

[in]	array	array to search in
[in]	size	length of array
[in]	key	key value to search for

Returns

index where the key-value occurs in the array

-1 if key-value not found

{
    for (int i = 0; i < size; ++i) 
    {
        if (array[i] == key) {
            return i;
        }
    }
 
    /* We reach here only in case element is not present in array, return an invalid entry in that case*/
    return -1;
}

main()

int main

(

void

)

Main function.

Returns

0 on exit

           {
    int mode = 0;
 
    std::cout << "Choose mode\n";
    std::cout << "Self-test mode (1), interactive mode (2): ";
 
    std::cin >> mode;
 
    if (mode == 2) {
        int size = 0;
        std::cout << "\nEnter the size of the array: ";
        std::cin >> size;
 
        while ((size <= 1) || (size >= 30)) {
            std::cout << "Size cannot be less than zero. Please choose another value: ";
            std::cin >> size;
        }
 
        int *array = new int[size];
        int key = 0;
 
        // Input for the array elements
        std::cout << "Enter the array of " << size << " numbers: ";
        for (int i = 0; i < size; i++) {
            std::cin >> array[i];
        }
 
        std::cout << "\nEnter the number to be searched: ";
        std::cin >> key;
 
        int index = LinearSearch(array, size, key);
        if (index != -1)
        {
            std::cout << "Number found at index: " << index << "\n";
        } 
        else
        {
            std::cout << "Array element not found";
        }
        delete[] array;
    }
    else {
        tests();  // run self-test implementations
    }
    return 0;
}

tests()

static void tests ( )

static

Self-test implementations.

Returns

void

                    {
    int size = 4;
    int *array = new int[size];
    for (int i = 0; i < size; i++) {
        array[i] = i;
    }
 
    assert(LinearSearch(array, size, 0) == 0);
    assert(LinearSearch(array, size, 1) == 1);
    assert(LinearSearch(array, size, 2) == 2);
 
    size = 6;
    for (int i = 0; i < size; i++) {
        array[i] = i;
    }
 
    assert(LinearSearch(array, size, 3) == 3);
    assert(LinearSearch(array, size, 1) == 1);
    assert(LinearSearch(array, size, 5) == 5);
 
    std::cout << "All tests have successfully passed!\n";
    delete[] array; // free memory up
}