Find Minimum Element in an Array Using Linear Search in C++

Linear search is a sequential searching algorithm where we traverse every element within the input array and compare it with the key element to be found. The minimum element refers to the smallest element in the array.

In this article, we have an array of integers. Our task is to find the minimum element in that array using linear search. Here are the three approaches you can use to find the minimum element:

• Using Value
• Using Index
• Using Pointer

Using Value

In this approach, we will be using the value of the array to find the minimum element of an array using linear search. At the beginning, we assign the starting element as the minimum value to the minimum. Then we compare this value with each element of the array and replace the value if we find a value less than the existing element in the minimum.

Example

In this example, we have an unsorted array and we are using the array value to find the minimum element of the array:

#include<iostream>
using namespace std;
int main() {
   int i, minimum;
   int a[10] = {12, 6, 7, 9, 16, 15, 59, 2, 30, 1};
   int n = sizeof(a) / sizeof(a[0]);
   minimum = a[0];  //using array value

   cout<<"\nThe data element of array:";
   for(i = 0; i < n; i++) {
      cout<<" "<<a[i];

    // Linear Search
      if(minimum > a[i])
         minimum= a[i];
   }
   cout<<"\nMinimum Element: "<<minimum;
   return 0;
}

The output of the above code is given below:

The data element of array: 12 6 7 9 16 15 59 2 30 1
Minimum Element: 1

Using Index

This approach uses index value to search for the minimum element in the array. It is similar to the previous approach, the only difference is that we have used index instead of array value in this approach.

Example

The following example uses an index to find the minimum in the array using linear search:

#include <iostream>
using namespace std;

int minEle(int arr[], int n) {
    int minIndex = 0;   
    for(int i = 1; i < n; i++) {

        //Using index to compare
        if(arr[i] < arr[minIndex]) {
            minIndex = i;
        }
    }
    return arr[minIndex];
}

int main() {
    int arr[] = {7, 2, 8, 4, 1};
    int n = sizeof(arr)/sizeof(arr[0]);  

    cout << "Array elements: ";
    for(int i = 0; i < n; i++) {
        cout << arr[i] << " ";
    }
    
    cout << "\nMinimum element: " << minEle(arr, n);
    return 0;
}

The output of the above code is given below:

Array elements: 7 2 8 4 1 
Minimum element: 1

Using Pointer

In this approach, we have used a pointer to traverse the array and find the minimum element. We have assigned the first element as the minimum. Then we traverse through each element of the array using a pointer and compare the current element with minimum. We update the minimum, if a smaller element is found.

Example

In this example, we are using a pointer to compare each element and find the minimum value in the array:

#include <iostream>
using namespace std;

int minEle(int* arr, int n) {
    int min = *arr; // Initializing min with the first element
    for(int i = 1; i < n; i++) {

        // Using pointer to compare
        if(*(arr + i) < min) {
            min = *(arr + i);
        }
    }
    return min;
}

int main() {
    int arr[] = {52, 57, 40, 32, 43};
    int n = sizeof(arr)/sizeof(arr[0]);
    cout << "Array elements: ";
    for(int i = 0; i < n; i++) {
        cout << *(arr + i) << " "; 
    }

    cout << "\nMinimum element: " << minEle(arr, n);
    return 0;
}

The output of the above code is given below:

Array elements: 52 57 40 32 43 
Minimum element: 32