Bisection Method C++

#include<iostream>
#include<iomanip>
#include<cmath>
using namespace std;

float f(float x)
{
return(x*x*x*-4*x-9);
}
void bisect(float *x,float a,float b,int *itr)
{
*x=(a+b)/2;
++(*itr);
cout<<“Iteration no.”<<setw(3)<<*itr;
cout<<“X= ” <<setw(7)<<setprecision(5);
cout<<*x<<endl;
}

int main()
{
int itr=0,maxitr;
float x,a,b,aerr,x1;

cout<<“Enter the values of a, b, “;
cout<<“allowed error, maximum iteration”<<endl;
cin>>a>>b>>aerr>>maxitr;
cout<<fixed;
bisect(&x,a,b,&itr);

do
{
if(f(a)*f(x)<0)
b=x;
else
a=x;
bisect(&x1,a,b,&itr);

if(fabs(x1-x)<aerr)
{
cout<<"After "<<itr<<" iterations, root";
cout<<"="<<setw(6)<<setprecision(4);
cout<<x1<<endl;
return 0;
}
x=x1;
}while(itr < maxitr);

cout<<"Solution does not converge,";
cout<<"iterations not sufficient"<<endl;
return 1;
}