#include <cstdlib>
#include <iostream>
#include <math.h>

using namespace std;
double determine1(double,double);


int main()
{

    double x1,x2,C;
    bool answer=false;
    cout <<"輸入區間端點1:\n";
    cin >> x1;
    cout <<"輸入區間端點2:\n";
    cin >> x2;

    C=determine1(x1,x2);

    if(C>0)
    {
        cout <<"此方程式在此區間無解\n";
    }
    else if (C<0)
    {
       answer = true;
       cout <<"此方程式在此區間有解\n";
    }

    if(answer=true)
    {
       double temp;
       int i;
       for(i=0;i<=1000;i++)
       {
          temp=x1;
          x1=(x1+x2)/2;

          C=determine1(x1,x2);

          if(C>0)
          {
             x2=x1;
             x1=temp;
          }

        }

        cout << "解的近似值為:"<< x1 <<endl;
    }
    system("PAUSE");
    return 0;
}

double determine1(double x1,double x2)
{
    double A,B;
    A=pow(x1,3)+x1-1;
    B=pow(x2,3)+x2-1;
    return A*B;
}