C Exercises: Find majority element of an array

Last update on March 18 2025 13:23:36 (UTC/GMT +8 hours)

49. Majority Element (General)

Write a program in C to find the majority element of an array.

This task involves writing a C program to find and display the majority element in an array, which is the element that appears more than half the time. The program will take the array as input, analyze the frequency of each element, and then determine and print the majority element.

Visual Presentation:

C Exercises: Find majority element of an array

Sample Solution:

C Code:

# include <stdio.h>

// Function to find the majority element in the array
void findMajorityElement(int *arr1, int arr_size) 
{
    int i, mIndex = 0, ctr = 1;

    // Finding the potential majority element
    for(i = 1; i < arr_size; i++) 
    {
        if(arr1[mIndex] == arr1[i])
            ctr++;
        else
            ctr--;

        // Reset the candidate majority element when the counter reaches 0
        if(ctr == 0) 
        {
            mIndex = i;
            ctr = 1;
        }
    }

    ctr = 0;
    // Count the frequency of the potential majority element
    for (i = 0; i < arr_size; i++) 
    {
        if(arr1[i] == arr1[mIndex])
            ctr++; 
    }

    // Check if the frequency of the potential majority element is greater than arr_size/2
    if(ctr > (arr_size/2))
        printf("The majority of the Element : %d\n", arr1[mIndex]);
    else
        printf("No majority element found in the array.\n");
}

int main()
{
    int i;
    int arr1[] = {1, 3, 3, 7, 4, 3, 2, 3, 3};
    int ctr = sizeof(arr1) / sizeof(arr1[0]);	

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

    // Find the majority element in the array
    findMajorityElement(arr1, ctr);
    return 0;
}

Sample Output:

The given array is :  1  3  3  7  4  3  2  3  3  
The majority of the Element : 3

Flowchart:

For more Practice: Solve these Related Problems:

Write a C program to find the majority element in an array and display its frequency.
Write a C program to determine the majority element by sorting the array first and then scanning.
Write a C program to identify the majority element using recursion to divide the array.
Write a C program to check for a majority element and then compare it with the sum of all other elements.

C Programming Code Editor:

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