Enter the complex number expression: (5 + -6i) / (0 + 0i)
(5 + -6i) / (0 + 0i) is undefined. 

 我要把上面這個描述用進去....

我該怎麼做呢 ... 請幫幫忙 謝謝^^"

===========================================

main() {
  int a, b, c, d, e, f;
  char op;       /*加減乘除*/
  printf("Enter the fraction expression: ");
  scanf("%d/%d %c %d/%d", &a, &b, &op, &c, &d);
  printf("%d/%d %c %d/%d\n", a, b, op, c, d);
  if ( op == '*' ) {           /*當算乘法的時候*/
  e = a * c ;
  f = b * d ;
  printf("=%d/%d\n", e, f );
  }
  else if ( op == '+'){        /*當算加法的時候*/ 
  e = ( a * d ) + ( b * c );
  f = ( b * d );
  printf("=%d/%d\n", e, f );
  }
  else if ( op == '-'){        /*當算減法的時候*/ 
  e = ( a * d ) - ( b * c );
  f = ( b * d );
  printf("=%d/%d\n", e, f );
  }
  else if ( op == '/'){        /*當算除法的時候*/ 
  e = ( a * d );
  f = ( b * c );
  printf("=%d/%d\n", e, f );
  }
  system("Pause");
}