//ïðîòåñòîâàíî íà 2,5,10,20 ïîòîêàõ äî 10 âèäíî âèãðàø íà 20 âèäíî ïðîãðàø

#include <iostream>

#include <thread>

#include <ctime>

using namespace std;

void summing(int** m1, int** m2, int** res, int from, int to, int n)

{

for (int i = from;i < to;++i)

{

for (int j = 0;j < n;++j)

{

res[i][j] = m1[i][j] + m2[i][j];

}

}

}

void subtraction(int** m1, int** m2, int** res, int from, int to, int n)

{

for (int i = from;i < to;++i)

{

for (int j = 0;j < n;++j)

{

res[i][j] = m1[i][j] - m2[i][j];

}

}

}

void main()

{

srand(time(NULL));

int n = 5000;

srand(time(NULL));

int** arr1 = new int*[n];

int** arr2 = new int*[n];

for (int i = 0;i < n;++i)

{

arr1[i] = new int[n];

arr2[i] = new int[n];

}

int** res1 = new int*[n];

int** res2 = new int*[n];

for (int i = 0;i < n;++i)

{

res1[i] = new int[n];

res2[i] = new int[n];

}

for (int i = 0;i < n;++i)

{

for (int j = 0;j < n;++j)

{

arr1[i][j] = rand() % 100;

arr2[i][j] = rand() % 100;

}

}

int numberOfThreads = 5;

thread* arr = new thread[numberOfThreads];

int from = 0;

int step = n/numberOfThreads;

int to = step;

clock_t start_time = clock();

for (int i = 0;i < numberOfThreads;++i)

{

arr[i] = thread(summing,arr1, arr2, res1, from, to, n);

arr[i].join();

from += step ;

to += step ;

}

cout <<"summing time for n=5000 and numberof threads="<<numberOfThreads<<" "<< (float)clock() - start_time << endl;

/*for (int i = 0;i < n;++i)

{

for (int j = 0;j < n;++j)

{

cout << res1[i][j] << " ";

}

cout << endl;

}*/

from = 0;

to = step;

start_time = clock();

for (int i = 0;i < numberOfThreads;++i)

{

arr[i] = thread(subtraction, arr1, arr2, res1, from, to, n);

arr[i].join();

from += step;

to += step;

}

cout << "subtraction time for n=5000 and numberof threads=" << numberOfThreads << " " << (float)clock() - start_time << endl;

system("pause");

}