You can combine more than one condition of you are performing a test which needs to consider several things. You use the logical operators to do this. They are && and ||

&& means AND. You would use it in the following way:

if ( (i==99) && (j==100) ) ...

The condition would be true if i is equal to 99 and j is equal to 100.

|| means OR. You would use this in the following way:

if ( (i==100) || (j==101) ) ...

The condition would be true if i is equal to 100 or j is equal to 101.

You can combine as many conditions as you like in this way, and you can use brackets to indicate precedence.

See if you can work out what the program on the right would do.

/*  Complex Expression  */
void main ( void )
{
  int count = 1 ;
  int value = 100 ;
  if ((count == 1)&&(value < 100))
  {
    /* get here if count is */
    /* 1 and value is less  */
    /* than 100             */
  }
}