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--- notes:data:spring2024:projects:waq0 [2024/04/16 13:42] – [Doubly Linked Queue] rspringe
+++ notes:data:spring2024:projects:waq0 [2024/04/16 14:00] (current) – [FIFO] rspringe
@@ Line 4: / Line 4: @@
 ====FIFO====
+FIFO stands for "First In First Out", and it is the way that data is removed from a queue.
+If the Stack can be thought of as a stack of papers, then a queue can be thought of as a line at a bank or at a grocery store checkout.
+For a stack of papers, if you wanted to place a new paper on the stack, then you would put it on top of the stack. Then, if you wanted to take a sheet of paper, then you would generally take one from the top of the stack, leaving the bottom of the stack as it was.
+For a line of people, anyone new who joins the line will have to stop and wait at the end of the line. Then, when the next person is called from the line, the person who is waiting at the very front of the line will go forward and leave the queue.
 ====Function to Create a Queue====
 Here is what the pseudocode for creating a basic doubly linked queue would look like:
@@ Line 15: / Line 21: @@
     nextElement pointer to next Obj in queue
-struct Queue:
+struct/class Queue:
     firstElement pointer to bottom of queue
     lastElement pointer to top of queue
+Initialize prevObj
+Initialize nextObj
+add function (Obj* obj):
+    Set prevObj and nextObj to obj's previous element and next element, respectively
+    if queue is empty:
+        Set queue's first element and last element to obj
+        Set obj's prev element to NULL
+    else:
+        Set obj's previous element to queue's last element
+        Set queue's last element's next element to obj
+        Set queue's last element to obj
+    Set obj's next element to NULL
+    Point prevObj and nextObj to each other
+remove function:
+    Grab queue's first element
+    Set nextObj to this obj's next element (second in queue)
+    Set queue's first element to nextObj
+    Set nextObj's previous element to NULL
+    Set obj's next element to NULL
+    return obj
+Main Code:
+    Initialize Queue
+    Initialize elements
+    Use add and remove functions throughout code
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