I was trying to make a function to take the square root of a number (which does not work completely, yet), but while I was coding it, I found an strange "error", this is the code:
#include <iostream>
#include <cstdlib>
using namespace std;
int main()
{
double number;
cin >> number;
double i2 =0, i=0;
while( (i*i) < number )
{
if (i == 0)
i = 0.1;
else
i *= 2;
}
i2 = i/4.0;
while ((i * i) > number)
{
i -= i2;
i2 /= 2.0;
}
cout << i << endl;
system("PAUSE");
return 0;
}Everything was working properly until I realized that the last loop iterated one more time than I expected. I tried to use 4 as "number", it would eventually become 2, which then would be tested in: while ((i * i) > number), I supposed that it would make the loop become false and end with i having a value of 2, but it instead iterated one more time, leaving i with a value of 1.8, finally I tried using floats (which seemed a waste of time for me, since double is more precise, or at least that is what I had been told), my surprise was that it DID work, and I do not know why there is a problem using doubles. I would like to know if there is a special reason. Thank you for reading ;).
PD: I posted the "bad" code so you could check it.
