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> Programming and Scripting > Blueprint Visual Scripting > Basic Scripting > Blueprint Set Nodes > Union

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Union

Performs a union of two Sets, assigning the union to a resultant Set.

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Inputs
Outputs
Example Usage

The Union node takes the union of items found in two Sets, assigning the union to a Resultant Set, with the result containing items found in both Set A and Set B. Visually, the intersection of Set A and Set B looks like the following diagram, where the intersection of Set A and Set B contains items that are common to both Sets.

For illustrative purposes, let's say that you have two string type Sets, Set A and Set B, both of which are defined below.

Set A = {"Item 1", "Item 2", "Item 3", "Item 4", "Item 5"}
Set B = {"Item 4", "Item 5", "Item 6", "Item 7", "Item 8"}

The following table shows you the result, which contains the union of Set A and Set B (symbolically represented as A ∪ B ).


Set A	Set B	Resultant Set (A ∪ B)
`Item 1`	`Item 4`	`Item 1`
`Item 2`	`Item 5`	`Item 2`
`Item 3`	`Item 6`	`Item 3`
`Item 4`	`Item 7`	`Item 4`
`Item 5`	`Item 8`	`Item 5`
		`Item 6`
		`Item 7`
		`Item 8`

A Set is a collection of unique items, which means that duplicate items will be eliminated from the Resultant Set.

Inputs


Pin Location	Name	Description
	(In) Exec	Input execution pin.
	A	One Set to union.
	B	The other Set to union.

Outputs


Pin Location	Name	Description
	(Out) Exec	Output execution pin.
	Result	The Set containing the resultant union.

Example Usage

Footnote

Symbolically, this operation is represented as A ∪ B = { x | x ∈ A ∨ x ∈ B }, wherein this node is performing a logical OR operation between elements in Set A and elements in Set B.