for (i = 0; i < m; i++)
    {
        for (j = 0; j < k; j++)
        {
            tabC[i][j] = 0;
            for (s = 0; s < n; s++)
            {
                tabC[i][j] =tabC[i][j] + tabA[i][s] * tabB[s][j];
            }
        }
        putchar('\n');
    }