C program to count number of digits in a number using recursion For didactic purposes, hence, I would like to not use the functions from math. Dec 2, 2020 · Here is the source code of the C Program to Count the number of digits in a number using recursion. Examples: Input: 12345 Output: 15 Explanation: Sum of digits → 1 + 2 + 3 + 4 + 5 = 15 Input: 45632 Output: 20 Approach: To understand the algorithm, consider the number 12345 and refer to the illustration below. A very simple and beginner-friendly explanation for students preparing for See full list on tutorialgateway. How to count number of digits in a number using iterative approach. Test Data : Input the number of elements to store in the array :3 Input 3 numbers of elements in the array in ascending order : element - 0 : 15 element - 1 : 25 element - 2 : 35 Input the number to search : 35 Expected Output : The search number found Write a C program to count the number of digits in an integer using for loop, while loop, without using recursion, and using recursion. To see this, print size after initializing it. org Nov 1, 2025 · C programming, exercises, solution : Write a program in C to count the digits of a given number using recursion. To fix this, make size static; it will then use the same static variable each time you call the function. In this tutorial, I have explained java program to count number of digits in a number using recursion. As you are printing size at the end of the function, it simply gives the value of Oct 3, 2025 · Given a number n, the task is to return the count of digits in this number. Nov 1, 2025 · 21. In this short video, you will learn how to write a recursive function in C to count the number of digits in a number. Mar 17, 2025 · Given a number, we need to find sum of its digits using recursion. Binary Search Recursion Variants Write a program in C for binary search using recursion. Example: Input: n = 1567 Output: 4 Explanation: There are 4 digits in 1567, which are 1, 5, 6 and 7. 5K subscribers 125. Extract the last digit: 12345 % 10 = 5, pass 1234 to the next step. Jul 11, 2024 · Explanation: The count of digit in 12345 = 5 Input: N = 23451452 Output: 8 Explanation: The count of digits in 23451452 = 8 Methods to Count Digits of a Number There are a few methods to count the digits of a number mentioned below: Using Loops Logarithmic Approach Using Recursion Using Repeated Multiplication By Dividing with Powers of Two 1. . For example: If the user enters 2319, the output of the program will be 4. Apr 28, 2023 · Recursion is a powerful technique in programming that involves calling a function within itself, and this tutorial will show you how to use it to count the digits of a number. Input: n = 255 Output: 3 Explanation: There are 3 digits in 256, which are 2, 5 and 5. In this program, we are reading an integer number and counting the total digits, here countDigits () is a recursion function which is taking number as an argument and returning the count after recursion process. h, as presented in: Jan 20, 2018 · First, you are declaring a new local variable called size each time the function is called. Jun 11, 2017 · In order to learn recursion, I want to count the number of decimal digits that compose an integer. By the end, you'll have a solid understanding of recursion in C++ and how to apply it to solve programming problems related to counting digits. This program takes an integer from the user and calculates the number of digits. Instead, you can simply do return 1 + digit(n / 10) or new = n / 10 return 1 + digit(new) Counting number of digits in an integer through recursion Asked 11 years, 9 months ago Modified 2 years, 6 months ago Viewed 10k times Jul 12, 2025 · Approach: The idea is to use recursion to extract the least significant digit of the number in each step and Check that the digit extracted is equal to the given digit is K or not. Finally, recurse for checking the next digits of the number by computing the integer division of that number by 10. This has no relation to the 'size' defined in the calling function. Counting digits of a number using recursion In this program, we are reading an integer number and counting the total digits, here countDigits () is a recursion function which is taking number as an argument and returning the count after recursion process. Return the count by adding 1 at each recursion level until the base case (n == 0) is reached. Below is the implementation of the above approach: Jan 2, 2018 · 24 Recursion | Count number of digits in a number using recursion in C | by Sanjay Gupta Skill Horizon by Sanjay Gupta 94. Use the recursion function countDigits () to count digits by dividing the number by 10 repeatedly. So, you are ignoring 1 digit in every recursive call. Dec 2, 2014 · The problem is, new = n/10 return 1 + digit(new/10) You are already dividing the number by 10, in new = n / 10, which reduces the last digit and you are again dividing it by 10 before calling digit. Convert the number to positive if it's negative to simplify digit counting. xpuahsg fauswm spvlz uud whuayx ancnkeq jhkmlplg vrw gogg undmic bzashk lfrxc rukedq kff vlmx