"Stack" (Data Structure)

"Stack"

represents a stack of expressions.

Details

A stack is a collection of elements that supports last-in, first-out insertion and removal:

	CreateDataStructure["Stack"]	create a new empty "Stack"
	CreateDataStructure["Stack",elems]	create a new "Stack" containing elems
	Typed[x,"Stack"]	give x the type "Stack"

ds["Copy"]	return a copy of ds	time: O(n)
ds["DropAll"]	drop all the elements from ds	time: O(n)
ds["Elements"]	return a list of the elements of ds	time: O(n)
ds["EmptyQ"]	True, if the ds is empty	time: O(1)
ds["Fold",fun]	apply fun to the elements of ds, accumulating a result	time: O(n)
ds["Fold",fun,init]	apply fun to the elements of ds, starting with init, accumulating a result	time: O(n)
ds["Length"]	number of elements in ds	time: O(1)
ds["Peek"]	last element in ds	time: O(1)
ds["Pop"]	remove the last element in ds and return it	time: O(1)
ds["Push",x]	add x to the end of ds	time: O(1)
ds["PushList",elems]	add elems to the end of ds	time: O(nelems)
ds["Visualization"]	return a visualization of ds	time: O(n)

	ds_i===ds_j	True, if ds_i equals ds_j
	FullForm[ds]	full form of ds
	Information[ds]	information about ds
	InputForm[ds]	input form of ds
	Normal[ds]	convert ds to a normal expression

open allclose all

A new "Stack" can be created with CreateDataStructure:

ds is initially empty:

Add an element to ds:

ds is no longer empty:

It has one element:

Add another element and peek. This shows the last element:

Remove the last element and return it:

Return an expression version of ds:

It is fast to push elements onto a stack:

A visualization of the data structure can be generated:

Sum all elements:

A new "Stack" can be created with CreateDataStructure:

Information about the data structure ds:

Top