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Find out the element which occurs once in the array

Here is the program to find out the element which occurs once in the array using C:

C program to find the element which occurs once in the array

#include <stdio.h>

// Function to find unique element
int findUniqueElement(int arr[], int arr_size) {
  int unique = 0;
  for (int i = 0; i < arr_size; i++) {
    unique ^= arr[i];
  }
  return unique;
}

// The main code
int main() {
  // array of the numbers
  int arr[] = {20, 30, 50, 40, 50, 30, 40};

  // length of the array
  int arr_size = sizeof(arr) / sizeof(arr[0]);

  // finding unique element
  int uniqueElement = findUniqueElement(arr, arr_size);

  printf("Element that occurs once in the array is: %d\n", uniqueElement);

  return 0;
}

Output

Element that occurs once in the array is: 20