C Exercises: Find the number occurring odd number of times in an array

C Array: Exercise-34 with Solution

Write a program in C to find the number occurring odd number of times in an array.
All numbers occur even number of times except one number which occurs odd number of times.

Visual Presentation:

Sample Solution:

C Code:

#include <stdio.h>

// Function to find the element occurring odd number of times in the array using XOR operation
int findOddCountElem(int *arr1, int n) {
    int i, ResultXor = 0;

    // Performing XOR operation on all array elements
    for (i = 0; i < n; i++) {
        ResultXor = ResultXor ^ arr1[i];
    }
    return ResultXor; // Returns the element occurring odd number of times
}

// Main function
int main() {
    int i;
    int arr1[] = {8, 3, 8, 5, 4, 3, 4, 3, 5};
    int ctr = sizeof(arr1) / sizeof(arr1[0]);

    // Display the given array
    printf("The given array is :  ");
    for (i = 0; i < ctr; i++) {
        printf("%d  ", arr1[i]);
    }
    printf("\n");

    // Function call to find the element occurring odd number of times
    printf("Number of odd number occur(s) : %d times.\n", findOddCountElem(arr1, ctr));

    return 0;
}

Sample Output:

The given array is :  8  3  8  5  4  3  4  3  5  
Number of odd number occur(s) : 3 times. 

Flowchart :

C Programming Code Editor:

Previous: Write a program in C to find the majority element of an array.
Next: Write a program in C to find the largest sum of contiguous subarray of an array.