C++实现二分法求解方程

#include <stdio.h>
#include <iostream>
using namespace std;

double f(double x)
{
return x*x*x-x-1;
}

double func(double a,double b,int n)
{
double c;
int i=0;
while(i<n)
{
c=(a+b)/2;
if(f(c)==0) return c;
if(f(c)*f(a)>0)
a=c;
else
b=c;
i++;
}
return c;
}

int main()
{
double a,b;
cout<<"Please input the value a:"<<endl;
cin>>a;
cout<<"Please input the value b:"<<endl;
cin>>b;
int n=1000;
if(f(a)*f(b)> 0 ) cout<<"No result !"<<endl;
if(f(a)==0) cout<<a<<endl;
else if(f(b)==0) cout<<b<<endl;
cout<<"The result of x value: /n";
else cout<<func(a,b,n)<<endl;
char c;
cin>>c;
return 0;
}