该程序找到代码中定义的函数 f 的第一个根。这个函数有 5 个根。(x=1,2,3,4,5) 我希望找到该程序中的所有根并将它们打印到屏幕上。在 main 函数中，您可以看到我试图编写一个 while 循环来执行此操作（在下面的代码中注释掉）。但这不起作用，它只是将相同的结果无限地打印到屏幕上。任何帮助，将不胜感激。

// This program finds the roots of a polynomial using the half interval search method

#include <iostream> //preprocessor directive needed in order to use std::cout
                //and std::cin
#include <iomanip> //preprocessor directive needed in order to use
               //a manipulator which uses an argument

using namespace std; //avoids having to uses std:: with cout and cin

//declare the variables
const double a = 0.0, b = 6.0; //limits for f()
double px = 1e-6;              //define the precision
double x = a, dx = 1.0;        //start value and initial interval
double root;

//prototypes for f()
double f (double x);
double halfIntervalSearch (double a, double b, double dx, double px); 

int main (int argc, char* argv[])
{
    //Inform the user what the program does
    cout << "This program finds the roots of\n"
    "f(x) = x^5 - 15x^4 + 85x^3 - 225x^2 + 274x -120 = 0\n"
    "which is bracketed by [" << a << ", " << b <<
    "] using the half interval search method." << endl;

    cout << "Searching...\n"; //Lets user know what is happening

    root = halfIntervalSearch(a,b,dx,px); //pass the variable

    //print out results
    //while (x <= b)
    {
          //x = root + 2*px; //reset value of x
          cout << "\nRoot at x = " << setw(10) << setprecision(7) << fixed 
          << root << " of value " << f(root) << endl;      
    }    
    //allow user to see the results before ending the program
    cout << "\n\nPress Enter to end the program";
    cin.get();
}

////////////////////////////////////////////////////////////////////////////////
//define f()
double f (double x)
{
       return (x*x*x*x*x)-(15*x*x*x*x)+(85*x*x*x)-(225*x*x)+(274*x)-120;  
}
///////////////////////////////////////////////////////////////////////////////
//define halfIntervalSearch()
double halfIntervalSearch (double a, double b, double dx, double px)
{
       while ((x <= b) && (dx > px))
       {
             while ( f(x)* f(x+dx) > 0) //while there are no roots 
             {
                   //keep track while program finds roots
                   cout << "x = " << setw(18) << x << " | dx = " << setw(15) 
                        << right << dx << endl;
                   x += dx; //step forward
             }

             dx = dx/2; //half the interval
       }
       return x;
}