simpson method

[m4k4v3l1]

#include <stdio.h>
#include <conio.h>

//**********************************
{
int main();
double a,f;
int n;
//Duomenys----------------
printf("a=0");
scanf("%lf", &a);
//------------------------
 printf("n=7");
 scanf("lf",&n);
 f=simpson(a ,b , n); // Integralas
 //Rezultatas----------------
 printf("b=1");
 scanf("%lf", &b);
}
//**********************************
double simpson(double a, double b, int n)
{

f=fk(x); //funkcija

}
//**********************************
double fk(double x)
{
return x * x;
}
//********************************** 

I need to count integral of this program:
I should get results:
a=0
b=1
n=7
integral=0.333
but I don't know how to do few things.Help please.

[nathandelane]

What is it, more specifically, that you don't know how to do/need help on?

[m4k4v3l1]

I need to get answer as showen , but something is wrong in my program , I need somebody to fix it.

[anilpanicker]

simpson rule on the web:
http://en.wikipedia.org/wiki/Simpson's_rule

You can also code a simpson composite rule in the same maner

#include <stdio.h>
#include <conio.h>
#include <cstdlib>

double simpson(double a, double b, int n);
double fk(double x);
//**********************************
int main()
{

double a,f,b;
int n;
//Duomenys----------------
printf("Enter value of a, example a=0\n a:");
scanf("%lf", &a);
//------------------------
printf("Enter value of n, example n=7\n n:");
 scanf("%d",&n);
 printf ("Enter Value of b, example b=1\nb:");
 scanf("%lf", &b);
 f=simpson(a ,b , n); // Integralas
 //Rezultatas----------------
 printf("The result is f=%7.2f\n",f);

}
//**********************************
double simpson(double a, double b, int n)
{
	double c= (a+b)/2.0;
	double h3= abs(b-a)/6.0;
	double result= h3*(fk(a)+4.0*fk(c)+fk(b));
	return result;



}
//**********************************
double fk(double x)
{
return x * x;
}