C + + skillfully open the square of the implementation code _c language

You can guess a number, such as 1.5, and then divide by 2 by this number. If we're right, the result of division is necessarily the same as the number we're guessing. The more accurate we speculate, the closer the result of division is to the number of guesses.

According to this principle, as long as we take the guessing number and the median of the feedback number as a new guess number, it will be closer to the answer! This method of calculation is called "iterative method".

Copy Code code as follows:

Double n = 2;
Double A = 0;
Double b = n;
while (Fabs (a-b) >1e-15)//when calculated to number and guess number within a certain error output guess number
{
A = (a+b)/2; The guessing number is half of n
b = n/A;
}
printf ("%f\n", a);