check for duplicates c

To check for duplicates in an array in the C programming language, you can follow these steps:

1. Declare an array of elements.
2. Iterate through each element of the array.
3. For each element, compare it with all the subsequent elements.
4. If a duplicate element is found, print a message indicating the presence of a duplicate.
5. Continue the iteration until all the elements have been checked.

Here's an example code snippet that demonstrates this process:

#include <stdio.h>

int main() {
   int arr[] = {1, 2, 3, 4, 5, 2, 6, 7, 8, 8};
   int length = sizeof(arr) / sizeof(arr[0]);
   int i, j;

   for (i = 0; i < length - 1; i++) {
      for (j = i + 1; j < length; j++) {
         if (arr[i] == arr[j]) {
            printf("Duplicate found: %d\n", arr[i]);
         }
      }
   }

   return 0;
}

In this code, we have an array arr with some elements. We calculate the length of the array using the formula sizeof(arr) / sizeof(arr[0]). Then, we use two nested loops to compare each element with all the subsequent elements. If a duplicate is found, we print a message indicating the duplicate element.

Note: It's important to ensure that the array is sorted before checking for duplicates using this approach. If the array is not sorted, you may need to use a different approach, such as using a hash table or sorting the array first.