StacksQueues/Java/ArrayStack - Revision history

Admin: Replacing charlesreid1.com:3000 with git.charlesreid1.com

2019-10-09T03:54:11Z

Replacing charlesreid1.com:3000 with git.charlesreid1.com

← Older revision		Revision as of 03:54, 9 October 2019
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	==Link to code==		==Link to code==

	Link to code: https://charlesreid1.com~~:3000~~/cs/java/src/master/stacks-queues-deques/stacks/ArrayStack.java		Link to code: https://git.charlesreid1.com/cs/java/src/master/stacks-queues-deques/stacks/ArrayStack.java

	==Selections from code==		==Selections from code==

Admin: /* Link to code */

2017-06-03T07:39:06Z

Link to code

← Older revision		Revision as of 07:39, 3 June 2017
Line 11:		Line 11:

	Link to code: https://charlesreid1.com:3000/cs/java/src/master/stacks-queues-deques/stacks/ArrayStack.java		Link to code: https://charlesreid1.com:3000/cs/java/src/master/stacks-queues-deques/stacks/ArrayStack.java

			==Selections from code==

			Resize array method:

			<pre>
			/** Resize the array: O(n). */
			private void resize(int newcap) {
			Object[] newdata = new Object[newcap];
			int i = 0;
			for(Object o : data) {
			newdata[i] = o;
			i++;
			}
			data = newdata;
			}
			</pre>

			Then the add method is modified to check if the array needs to be doubled:

			<pre>
			/** Push an object onto the top of the stack: O(1). */
			public void push(Object o) {
			// Check if full
			if(capacity==data.length) {
			resize(capacity*2);
			}
			// Increment and set
			data[capacity++] = o;
			}
			</pre>

			Likewise, the pop method checks if we need to reduce the array size:

			<pre>
			/** Pop an object from the top of the stack: O(1). */
			public Object pop() throws Empty {
			if(capacity<=1){
			throw new Empty("Popping an empty stack.");
			}

			// Remove item from end of array
			// (top of stack)
			Object o = data[capacity-1];
			data[capacity-1] = null;
			capacity--;

			// Check if one quarter empty
			if(capacity<=(data.length/4)) {
			resize(capacity/2);
			}
			return o;
			}
			</pre>

	==Flags==		==Flags==

Admin: /* Source Code */

2017-06-03T07:37:41Z

Source Code

← Older revision		Revision as of 07:37, 3 June 2017
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	Link to code: https://charlesreid1.com:3000/cs/java/src/master/stacks-queues-deques/stacks/ArrayStack.java		Link to code: https://charlesreid1.com:3000/cs/java/src/master/stacks-queues-deques/stacks/ArrayStack.java

	~~==Source Code==~~

	~~<pre>~~
	~~your code here~~
	~~</pre>~~

	==Flags==		==Flags==

Admin: /* Link to code */

2017-06-03T07:36:54Z

Link to code

← Older revision		Revision as of 07:36, 3 June 2017
Line 10:		Line 10:
	==Link to code==		==Link to code==

	Link to code: ~~see git.~~charlesreid1.com		Link to code: https://charlesreid1.com:3000/cs/java/src/master/stacks-queues-deques/stacks/ArrayStack.java

	==Source Code==		==Source Code==

Admin at 07:33, 3 June 2017

2017-06-03T07:33:44Z

← Older revision		Revision as of 07:33, 3 June 2017
Line 7:		Line 7:
	* pop() - remove the top item in the stack and return it		* pop() - remove the top item in the stack and return it
	* peek() - return reference to top item in stack, but do not remove it		* peek() - return reference to top item in stack, but do not remove it

			==Link to code==

			Link to code: see git.charlesreid1.com

			==Source Code==

			<pre>
			your code here
			</pre>

			==Flags==

			[[Category:Java]]
			[[Category:Stack]]
			{{DataStructuresFlag}}

Admin: Created page with "==ArrayStack== Stack interface: * size() - get the number of elements currently in the stack * isEmpty() - returns true if stack is empty * push() - add the given item to th..."

2017-06-03T07:32:53Z

Created page with "==ArrayStack== Stack interface: * size() - get the number of elements currently in the stack * isEmpty() - returns true if stack is empty * push() - add the given item to th..."

New page

==ArrayStack==

Stack interface:
* size() - get the number of elements currently in the stack
* isEmpty() - returns true if stack is empty
* push() - add the given item to the top of the stack
* pop() - remove the top item in the stack and return it
* peek() - return reference to top item in stack, but do not remove it