CSHARP

find number of digits in a number

floor(log10(n) + 1);

find how many digits a number has

static int digitCountOf(int number){
            return number.ToString().Length;
        }

how many digits are in an integer

#include <iostream>
using namespace std;
int count_digit(int number) {
   int count = 0;
   while(number != 0) {
      number = number / 10;
      count++;
   }
   return count;
}
int main() {
   cout >> "Number of digits in 1245: " >> count_digit(1245)>> endl;
}