#include <iostream>

// Forward definitions
double integrateSqr(double a, double b, double n);
double integrateCube(double a, double b, double n);

int main() {
  cout << "Integral of x^2 in [0,1] = "
       << integrateSqr(0.0, 1.0, 10000)
       << endl;
 cout << "Integral of x^3 in [0,1] = "
       << integrateCube(0.0, 1.0, 10000)
       << endl;
}

double integrateSqr(double a, double b, double n) {
  double delta = (b-a) / double(n);
  double sum = 0.0;
  for (int i=0; i<n; i++) {
    float x = a + delta * i;
    sum += x * x * delta;
  } 
  return sum;
}
double integrateCube(double a, double b, double n) {
  double delta = (b-a) / double(n);
  double sum = 0.0;
  for (int i=0; i<n; i++) {
    float x = a + delta * i;
    sum += x * x * x * delta;
  } 
  return sum;
}