Linear Search in C

Problem Statement: Given an array, and an element num the task is to find if num is present in the given array or not. If present print the index of the element or print -1.


Example 1:
Input: arr[]= 1 2 3 4 5, num = 3
Output: 2
Explanation: 3 is present in the 2nd index

Example 2:
Input: arr[]= 5 4 3 2 1, num = 5
Output: 0
Explanation: 5 is present in the 0th index


DisclaimerDon’t jump directly to the solution, try it out yourself first.


  • Given an array
  • We will traverse the whole array and see if the element is present in the array or not
  • If found we will print the index of the element
  • Otherwise, we will print -1.

C Program


int search(int arr[],int n,int num)
    int i;
        return i;
    return -1;
int main()
    int arr[]={1,2,3,4,5};
    int num = 4;
    int n = sizeof(arr)/sizeof(arr[0]);
    int val = search(arr,n,num);

Output: 3

Time Complexity: O(n), where n is the length of the array.

Space Complexity: O(1)

Special thanks to Subhrajit Das for contributing to this article on takeUforward. If you also wish to share your knowledge with the takeUforward fam, please check out this article