C Program to Remove Every Alternate Digit from a Number


This article will explore c program to remove every alternate digit from a number.

In the realm of computer programming, there are numerous algorithms and techniques that can be employed to solve various problems efficiently.

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One such problem involves removing every alternate digit from a given number. This article will delve into the intricacies of writing a C program to tackle this challenge.

By following along, you will gain insights into the logic behind this program and enhance your understanding of C programming.

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C Program to Remove Every Alternate Digit from a Number

To begin, let’s take a look at the C program that removes every alternate digit from a given number:

#include <stdio.h>

int removeAlternateDigits(int num) {
    int result = 0;
    int multiplier = 1;

    while (num != 0) {
        int digit = num % 10;
        num /= 10;

        if (num % 10 != 0) {
            result += digit * multiplier;
            multiplier *= 10;

    return result;

int main() {
    int number;
    printf("Enter a number: ");
    scanf("%d", &number);
    int modifiedNumber = removeAlternateDigits(number);
    printf("Number with alternate digits removed: %d", modifiedNumber);
    return 0;

Understanding the Program

Now, let’s delve into the workings of the program. The removeAlternateDigits function takes an integer as input and returns another integer with every alternate digit removed.

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Here’s a step-by-step breakdown of the logic:

  1. Initialize result and multiplier to zero and one, respectively.
  2. Begin a loop that continues until the given number becomes zero.
  3. Extract the rightmost digit of the number using the modulo operator and store it in the digit variable.
  4. Divide the number by 10 to remove the rightmost digit.
  5. Check if the next digit in the number is non-zero (i.e., an alternate digit). If it is, add the current digit to the result variable, multiplied by the multiplier, and update the multiplier by multiplying it by 10.
  6. Repeat steps 3-5 until the given number becomes zero.
  7. Return the result variable, which now contains the modified number with alternate digits removed.

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In the main function, we take user input, pass it to the removeAlternateDigits function, and display the modified number to the user.

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FAQs (Frequently Asked Questions)

Q: What is the purpose of this C program?

The purpose of this C program is to remove every alternate digit from a given number.

Q: Can this program handle negative numbers?

Yes, this program can handle negative numbers. The logic remains the same, regardless of the sign of the input number.

Q: How does the program determine which digits are alternate?

The program considers the rightmost digit of the number and checks if the next digit is non-zero. If it is, the current digit is considered alternate.

Q: Can this program handle decimal numbers?

No, this program is designed to work with integers only. Decimal numbers would require modifications to the program’s logic.

Q: Are there any limitations to the size of the input number?

The program can handle input numbers within the range of integers supported by the C programming language on your system.

Q: Is there an alternative approach to solving this problem?

Yes, there can be multiple approaches to solve this problem. This particular program follows a straightforward iterative approach.

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In conclusion, this article has provided you with a detailed understanding of how to write a C program to remove every alternate digit from a given number.

By dissecting the program’s logic and examining the step-by-step process, you can grasp the essence of the problem-solving techniques involved.

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Feel free to experiment with the program and explore different variations to further enhance your programming skills.

Remember, practice is key to mastery, so don’t hesitate to test your newfound knowledge with various input scenarios. Happy coding!

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