//用迭代法求近似平方根,青年人网和你一起学习：
#include <iostream>
#include <cmath>
using namespace std;
int main()
{
int flag = 0;
cout<<"please enter a number:";
double a = 0.0;
cin>>a;
const double EPSTLON = 1E-14;
double xnew = a;
double xold = 0.0;
do{
xold = xnew;
xnew = (xold + a/xold)/2;
}while(fabs(xnew - xold) > EPSTLON);
cout<<"the square root is:"<<xnew<<endl;
cin>>flag;
return 0;
}
责任编辑：小草
