⑪ C Program to Count Digits in a Number (With Program and Explanation)

 

🔢 C Program to Count Digits in a Number

📌 Problem Statement

Write a C program to count the total number of digits in a given integer number.

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🧠 Understanding the Logic

To count digits in a number:

1. Take a number as input.

2. Repeatedly divide the number by 10.

3. Each division removes the last digit.

4. Count how many times the division happens until the number becomes 0.

👉 Each division means one digit.

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✨ Special Case

• If the number is 0, the digit count is 1.

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🧾 Algorithm (Step by Step)

1. Start

2. Read the number n

3. If n == 0, set count = 1

4. Else

   • While n > 0

     • count++

     • n = n / 10

5. Print count

6. End

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💻 C Program to Count Digits

#include <stdio.h>

int main() {
    int num, count = 0;

    printf("Enter a number: ");
    scanf("%d", &num);

    // Special case when number is 0
    if (num == 0) {
        count = 1;
    } else {
        while (num != 0) {
            count++;
            num = num / 10;
        }
    }

    printf("Total number of digits = %d", count);

    return 0;
}

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📤 Sample Output Examples

▶ Example 1

Input

Enter a number: 12345

Output

Total number of digits = 5

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📚 Explanation of Code

• num / 10 removes the last digit

  • Example: 123 / 10 = 12

• Loop runs until num becomes 0

• Each loop increases count by 1

• Final count is the number of digits

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✅Conclusion

In this program, we learned how to Count Digits in a Number.
📘 C Programming Series – What’s Next?
👉 In the next post of this series, we will learn how to Swap Two Numbers (Without Temp) with complete explanation and output examples. Stay tuned! 🚀