C/C++ counting the number of decimals?

Question

Lets say that input from the user is a decimal number, ex. 5.2155 (having 4 decimal digits). It can be stored freely (int,double) etc.

Is there any

Answer 1

Something like this might work as well:

float i = 5.2154;
std::string s;
std::string t;
std::stringstream out;
out << i;
s = out.str();

t = s.substr(s.find(".")+1);
cout<<"number of decimal places: " << t.length();