MonteCarlo

#include <stdio.h>
#include <time.h>
#include "stdafx.h"
#include <stdlib.h>
#include <iostream>

using namespace std;

double Fun(double x) {
	return x*x;
}

double MonteCarlo(double a, double b) {

	srand(123975467);
	int countAll = 0;
	int countSquare = 0;
	double x;
	double y;
	double maxOfArea = (Fun(a) > Fun(b) ? Fun(a) : Fun(b));

	for (int i = 0; i < 1000000; i++) {
		x = ((rand() % 10000) / 10000.0) * (b - a) + a;
		y = ((rand() % 10000) / 10000.0) * maxOfArea;
		countAll += 1;
	//	printf("%lf %lf\n", x, y);
		if (y <= Fun(x)) {                 //y не больше х*х в данной точке
			countSquare = countSquare + 1;
	//		printf("aaa");
		}
	}
	printf("%d\n", countSquare);
	printf("%d\n", countAll);
	printf("Integral equals to ");

	double res = (b - a) * maxOfArea * countSquare / countAll;
	return res;
}