prog0108-demo

#include "stdafx.h"
#include <math.h>
double f1(double x)
{
    return x*x;
}
double f2(double x)
{
    return x*x*x;
}
double integral2(double a, double b, int n, double (*f) (double))
{
    double INTGRL = 0.0;
    double h = double((b - a) / n);
    for (double x = a; x <= b; x += h)
    {
        INTGRL += f(x - h / 2);
    }
    return INTGRL *= h;
}
int _tmain(int argc, _TCHAR* argv[])
{
    double a, b; int n;
    scanf_s("%lf %lf %d", &a, &b, &n);
    printf("%lf", integral2(a,b,n,sin));
    return 0;
}