formula for counts the integer's number of digits. code example
Example: how to find how many digits a number has in c++
#include <iostream>
#include <cmath>
unsigned int getNumberOfDigits (int i)
{
return i > 0 ? log10((double) i) + 1 : 1;
}
int main()
{
std::cout << "Number of digits: " << getNumberOfDigits(/*Example*/6738) << std::endl;
return 0;
}