写一段程序求出一个数的算术平方根:
#include<iostream>
using namespace std;
#define e 0.001
double sqrt(double a)
{
double x,y;
x=a/2;
y=x+1+e;
while(x-y>e||y-x>e)
{
y=x;
x=(x+a/x)/2;
}
return x;
}
int main()
{
double a;
cin>>a;
cout<<sqrt(a);
return 0;
}