#include <iostream>
#include <cmath>
#include <iomanip>

using namespace std;

int main()
{
    double t = 0;
    double eps;
    double x, y;
    cin>>x>>y>>eps;


    eps=eps*0.001;
    while(1)
    {
        double c = cos(t) - y;
        double d = sin(sqrt(t)) - x ;
        if( c*c+d*d > eps/2)
            t+=0.007;
        else
        {
            break;
        }
    }
    cout<<fixed<<setprecision(5)<<t;
    return 0;
}
Can someone tell what is wrong or give some tests?(my mail kilik94@yandex.ru) Thanks in advance!

Edited by author 07.12.2013 01:58

Why "> eps/2" ? May be "> eps**2"?