C program to count digits of a number using recursion :

Given an integer number and we have to count the digits using recursion using C program.

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.

Example:

    Input number: 1235
    Output:
    Total digits are: 4


Program to count digits in C using recursion code :







#include<stdio.h>

int count(int n)
{
  int cou,i;


  for(i=0;n!=0;i++){
        cou=n%10;

        n=n/10;
  }
  return i;
}

int main()
{
    int m;
    printf("Enter the number ");
    scanf("%d",&m);
    int bb=count(m);
    printf("count %d = %d",m,bb);
}













OR code:




#include<stdio.h>

int count(int n)
{
  int cou,i;
  int con=0;

  for(i=0;n!=0;i++){
        cou=n%10;
        con++;

        n=n/10;
  }
  return con;
}

int main()
{
    int m;
    printf("Enter the number ");
    scanf("%d",&m);
    int bb=count(m);
    printf("count %d = %d",m,bb);
}














OR code : 





#include <stdio.h>
 
//function to count digits
int countDigits(int num)
{
    static int count=0;
     
    if(num>0)
    {
        count++;
        countDigits(num/10);
    }
    else
    {
        return count;
    }
}
int main()
{
    int number;
    int count=0;
     
    printf("Enter a positive integer number: ");
    scanf("%d",&number);
     
    count=countDigits(number);
     
    printf("Total digits in number %d is: %d\n",number,count);
     
    return 0;
}