Thread: Checking for integer after square root

A less elegant, yet highly precise solution would have you simply convert the resultant value to a string and analyze that.

Code:

bool is_sqrt_int(double your_value) {
  std::ostringstream ostr;
  ostr << square_root_of(your_value);
  return ostr.str().find(".") == std::string::npos;
}

[edit]
As far as calculating the square root is concerned, I prefer Newton's iteration:

Code:

result = 1

for i = 1 to N
  result = (result + (value / result)) / 2

where N is the number of iterations you'd like. (The more iterations, the more precise the value, but I find just a few to be enough. Experiment yourself.)
[/edit]