text: #include <stdio.h>
  #include <string.h>
  #include <math.h>
  #include <stdlib.h>
  
  int main () {
  
      int number1;
      int number2;
      int number3;
      int number4;
      int diferenca;
  
      scanf ("%i%i%i%i", &number1, &number2, &number3, &number4);
      
      diferenca = ((number1 * number2)-(number3 * number4));
      
      printf ("DIFERENCA = %.i", diferenca);
  
      return 0;
  }