#include <stdio.h>
main() {
  float a11, a12, a21, a22, D;
  printf("Uneti clanove matrice: ");
  scanf("%f%f%f%f", &a11, &a12, &a21, &a22);
  D = (a11 * a22) - (a12 * a21);
  printf("D=%.4f\n", D);
}
