how to calculate the number of digits in a number in c code example

Example 1: print digits of a number in c

#include <stdio.h>

int main(){
    int num = 1024;

    while(num != 0){
        int digit = num % 10;
        num = num / 10;
        printf("%d\n", digit);
    }
  
    return 0;
}

Example 2: print digits of a number in c

#include <stdio.h>

int printDigits(int n){
  int digit;
  
  if(n < 10){//caso base
      digit = n;
      printf("%d\n", digit);
    }else{
      digit = printDigits(n/10);
      digit = printDigits(n%10);
    }

    return digit;
}

int main(){
    int num = 3467678;

    printDigits(num);

    return 0;
}