/**
***定步长复化Simpson解积分方程***
                                                                                   n-1
  定步长复化Simpson公式：Sn=h/6｛f(a)-f(b)+ ∑ ［ 4f(x(k-1/2)) + 2f(x(k)) ］｝
                                                                                   k=0
  属性：数值积分法
                       
  误差(精度)：I - Sn ≈ - 1/180 * (h*h*h*h)/2 * [ f'''(b) - f'''(a) ]
                      
        h = ( b - a ) / n

  《数值分析简明教程》-2 Editon -高等教育出版社- page 65 算法流程图
  
  代码维护：2005.6.14  DragonLord

**/

**/     
#include<iostream.h>
#include<math.h>
#include<stdio.h>
double f(double x)
{
    double f;
 if(x==0)f=1;      //                               1
 else f=sin(x)/x;  //   举例方程 I = ∫  sin(x)/x dx
 return f;         //                                  0
}
int main()
{
 double h,s,a,b,n,x;
 while(cin>>a>>b>>n)
 {
  h=(b-a)/n;
  s=f(a)-f(b);
  x=a;
  for(int i=0;i<n;i++)
  {
   x=x+h/2;
   s=s+4*f(x);
   
   x=x+h/2;
            s=s+2*f(x);
   
   printf("x=%.7f f(x)=%.7f,x=%.7f f(x)=%.7f s=%.7f\n",x-h/2,f(x-h/2),x,f(x),h*s/6);
  }
 }
 return 0;
}