#include <iostream>;
#include <string>;
#include <thread>;
using namespace std;


int volatile A1 = 0, B1 = 0, C1 = 0, D1 = 0;

void schet(int ot, int ido, int num){
	int s = 0, prom = 0;

	for (int i = ot; i <= ido; i++){
		prom = 0;

		for (int j = 0; j < i + 1000000000; j++){//этот цикл просто для задержки
			if (j % 2 == 0) prom = 1; else prom = -1;
		}

		s = s + i + prom;

		switch (num){
		case 1: A1 = s;
		case 2: B1 = s;
		case 3: C1 = s;
		case 4: D1 = s;
		}

	}

}

void main() {

	setlocale(LC_ALL, "");
	int k = 0, A = 0, B = 0, C = 0, D = 0;

	cout << "сумма от нуля до: ";
	cin >> k;
	A = k / 4;
	B = A + k / 4;
	C = B + k / 4;
	D = C + k / 4;
	cout << A << endl << B << endl << C << endl << D << endl;
	thread At(schet, 1, A, 1);
	thread Bt(schet, A+1, B, 2);
	thread Ct(schet, B+1, C, 3);
	thread Dt(schet, C+1, D, 4);

	if (At.joinable()){ At.join(); }
	if (Bt.joinable()){ Bt.join(); }
	if (Ct.joinable()){ Ct.join(); }
	if (Dt.joinable()){ Dt.join(); }

	//cout<< schet(1, k);
	cout << A1 + B1 + C1 + D1;
	system("pause>nul");

	}