cv2_ukol1.c

#include <stdio.h>
#include <stdlib.h>
#include <time.h>

int
main (int argc, char **argv)
{
  /* Matice. */
  int mat[3][3];
  int s_mat[5][3];

  /* Iteratory. */
  unsigned int row;
  unsigned int s_row;
  unsigned int col;

  /* Determinant. */
  int det;
  int cast_det;


  printf ("3x3 nahodna matice:\n\n");

  srand (time (NULL));
  for (row = 0; row < 3; row++)
    {
      for (col = 0; col < 3; col++)
        {
          mat[row][col] = (rand () % 199) - 99;
          printf("%4d", mat[row][col]);
        }
      putchar ('\n');
    }
  putchar ('\n');

  /* Vypocet determinantu pomoci vzorce. */
  det = mat[0][0] * mat[1][1] * mat[2][2]
      + mat[0][1] * mat[1][2] * mat[2][0]
      + mat[0][2] * mat[1][0] * mat[2][1]

      - mat[2][0] * mat[1][1] * mat[0][2]
      - mat[2][1] * mat[1][2] * mat[0][0]
      - mat[2][2] * mat[1][0] * mat[0][1];

  printf ("Determinant ziskan vzorcem: %d.\n\n\n", det);

  /* Vytvoreni Saurussovy matice. */
  printf ("Saurussova matice:\n\n");
  for (s_row = 0; s_row < 5; s_row++)
    {
      row = (s_row > 2) ? (s_row - 3) : s_row;
      for (col = 0; col < 3; col++)
        {
          s_mat[s_row][col] = mat[row][col];
          printf("%4d", s_mat[s_row][col]);
        }
      putchar ('\n');
    }
  putchar ('\n');

  /* Vypocet determinantu Saurussovim pravidlem. */
  det = 0;
  for (s_row = 0; s_row < 3; s_row++)
    {
      /* Zacinajic v bode [s_row][0], znasobit diagonalni prvky smerem dolu. */
      for (row = s_row, col = 0, cast_det = 1;
           col < 3;
           row++, col++)
        {
          cast_det *= s_mat[row][col];
        }
      det += cast_det;
    }
  for (s_row = 4; s_row > 1; s_row--)
    {
      /* Zacinajic v bode [s_row][0], znasobit diagonalni prvky smerem nahoru. */
      for (row = s_row, col = 0, cast_det = 1;
           col < 3;
           row--, col++)
        {
          cast_det *= s_mat[row][col];
        }
      det -= cast_det;
    }

  printf ("Determinant ziskan Saurussovim pravidlem: %d.\n\n\n", det);

  printf ("Zmacknite Enter pro ukonceni programu... ");
  getchar ();

  return 0;
}