TP T-5 Z4

#include <iostream>
#include <cmath>

double TrapeznoPravilo(double f(double), int a, int b, int n)
{
    double suma(0);
    for(int i(1); i <= n - 1; i++)
        suma+=f(a + ((double(b-a)/n)*i));
    return ((double(b-a)/n)*(f(double(a))/2 + f(double(b))/2 + suma));
}

int main()
{
    std::cout << TrapeznoPravilo([](double x) {return x*x*x;}, 0, 10, 200) << std::endl;
    std::cout << TrapeznoPravilo([](double x) {return std::sin(x);}, 0, 4*atan(1), 200) << std::endl;
    std::cout << TrapeznoPravilo([](double x) {return 1./x;}, 1, 2, 200) << std::endl;
    return 0;
}