Count even and odd numbers of an array in C++

In this tutorial, we will discuss the concept of the Count even and odd numbers of an array in C++

In this post, we are going to learn how to count even and odd numbers from the array of given numbers in the C++ programming language

First, we must understand how to identify odd or even numbers

What is Even or Odd

When the number is divided by 2 and the balance becomes zero and the above number is called as the even number – eg 2,4,6,8,10

and on the other sides when it is divided by 2 and balance becomes 1 they are called odd numbers or uneven numbers.

In my previous post, I have explained the various approaches to check whether the number is even or odd in C++ language

here, we will discuss how to count odd and even numbers from an array in the C++ programming language

There are three programs given below

The common procedure of these programs

Initially, Declare an integer type array with maximum capacity(100) and declare variables i, size, odd and even
The user will enter the size of the array and store in the variable size to define the array size
Then, the user enters all the elements of the array according to the array size using loops
After that, use a loop for iterating elements of the array
Finally, the following loops count even and odd number using if statements from the array

Count even and odd numbers in an array using for loop

Program 1

The program allows the user to enter the size of the array and receives the elements from the user.

Then, it will count the even and odd numbers from this array using for loop in C++

#include <iostream>
#include <conio.h>
using namespace std;

int main()
{
    int arr[100];
    int i,size,odd=0,even=0;

    //input the size of the array
    cout<<"Enter size of the array\n";
    cin>>size;//read input from the user for array size

    //input the array elements
    cout<<"\nEnter elements of the array\n\n";


    for(i=0; i<size; i++)
    {
        cout<<"Enter the element arr["<<i<<"] :";
        cin>>arr[i];//read input from the user for array elements

    }


    for(i=0; i<size; i++)
    {
        if(arr[i]%2==0)
        {
            even++;
        }
        else{
            odd++;
        }

    }

    cout<<"\nTotal even numbers of an array :"<<even<<"\n";
    cout<<"Total odd numbers of an array : "<<odd;
     getch();
    return 0;
}

When the above code is executed, it produces the following results

Enter the size of the array
10
Enter elements of the array

Enter the element arr[0] : 45
Enter the element arr[1] : 24
Enter the element arr[2] : 68
Enter the element arr[3] : 99
Enter the element arr[4] : 95
Enter the element arr[5] : 27
Enter the element arr[6] : 88
Enter the element arr[7] : 83
Enter the element arr[8] : 58
Enter the element arr[9] : 75

Total even numbers of an array :4
Total odd numbers of an array : 6

Program 2

Count even and odd numbers in an array using while loop

The program allows the user to enter the size of the array and receives the elements from the user.

Then, it will count the even and odd numbers from this array using while loop in C++

#include <iostream>
#include <conio.h>
using namespace std;

int main()
{
    int arr[100];
    int i,size,odd=0,even=0;

    //input the size of the array
    cout<<"Enter size of the array\n";
    cin>>size;//read the input from user for array size

    //input the array elements
    cout<<"\nEnter elements of the array\n\n";

    i=0;
    while(i<size)
    {
        cout<<"Enter the element arr["<<i<<"] :";
        cin>>arr[i];//read the input from user for array elements
         i++;
    }

     i=0;
    while(i<size)
    {
        if(arr[i]%2==0)
        {
            even++;
        }
        else{
            odd++;
        }
         i++;
    }

    cout<<"\nTotal even numbers of an array :"<<even<<"\n";
    cout<<"Total odd numbers of an array : "<<odd;
     getch();
    return 0;
}

When the above code is executed, it produces the following results

Enter the size of the array
10
Enter elements of the array

Enter the element arr[0] : 90
Enter the element arr[1] : 88
Enter the element arr[2] : 76
Enter the element arr[3] : 53
Enter the element arr[4] : 24
Enter the element arr[5] : 12
Enter the element arr[6] : 59
Enter the element arr[7] : 82
Enter the element arr[8] : 45
Enter the element arr[9] : 56

Total even numbers of an array :7
Total odd numbers of an array : 3

Program 3

Count even and odd numbers in an array using do while loop

The program allows the user to enter the size of the array and receives the elements from the user.

Then, it will count the even and odd numbers from this array using the do-while loop in C++

#include <iostream>
#include <conio.h>
using namespace std;

int main()
{
    int arr[100];
    int i,size,odd=0,even=0;

    //input the size of the array
    cout<<"Enter size of the array\n";
    cin>>size;//read the input from user for array size

    //input the array elements
    cout<<"\nEnter elements of the array\n\n";

    i=0;

     do{
        cout<<"Enter the element arr["<<i<<"] :";
        cin>>arr[i];//read the input from user for array elements
         i++;
    }while(i<size);

     i=0;

    do{
        if(arr[i]%2==0)
        {
            even++;
        }
        else{
            odd++;
        }
         i++;
    }while(i<size);

    cout<<"\nTotal even numbers of an array :"<<even<<"\n";
    cout<<"Total odd numbers of an array : "<<odd;
     getch();
    return 0;
}

When the above code is executed, it produces the following results

Enter the size of the array
10
Enter elements of the array

Enter the element arr[0] : 123
Enter the element arr[1] : 234
Enter the element arr[2] : 345
Enter the element arr[3] : 456
Enter the element arr[4] : 567
Enter the element arr[5] : 678
Enter the element arr[6] : 789
Enter the element arr[7] : 890
Enter the element arr[8] : 987
Enter the element arr[9] : 876

Total even numbers of an array :5
Total odd numbers of an array : 5

C code to compute even and odd numbers of an array

Suggested for you

while loop in C++

do-while loop in C++

If statements in C++

Single dimension array in C++

Example to Python program to check Prime number

Java program to display even and odd number in the given range