(1) any flight can be brought to the front of the queue ready for deleting(landing)
(2) any flight can be diverted to the back of the queue for another airport if the first airport is busy or on runway closed due to an accident.
(3)in the flight ID, there can only be one unique letter, for example A, a, B,b, we cannot have A,A, but we can have A,a

>the following three questions
You only have two questions.

>Any flight can be brought to the front of the queue ready for deleting
Since your queue is implemented with a linked list, you can easily splice out an item and replace it elsewhere:

these codes might help, i can't make it work

void moveToFront ( queue& q, const char data )
{
  nodePtr item;

  // Check to see if it's already at the front
  if ( data == q.front->data )
    return;

  // Find the item
  for ( nodePtr it = q.front; it->next != 0; it = it->next ) {
    if ( data == it->next->data ) {
      item = it->next;
      it->next = item->next;
      break;
    }
  }

  // Move to front
  item->next = q.front;
  q.front = item;
}

>In the flight ID, there can only be one unique letter
For each new ID, traverse the queue and make sure it doesn't already exist:

bool isUnique ( queue& q, const char data )
{
  for ( nodePtr it = q.front; it != 0; it = it->next ) {
    if ( data == it->data )
      return false;
  }

  return true;
}
Code removed at OP's request
Code removed at OP's request

Code tags added and ugly ass colors removed. -Narue

how do i delete the code i put on here

>how do i delete the code i put on here
You ask a mod to remove selected parts of your post, or the entire post if you feel the need.

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