Swap (computer programming)

In <a href="/facts/Computer_programming/QmSsFnu0">computer programming</a>, the act of swapping two <a href="/facts/Variable_(programming)/VoCKtwml">variables</a> refers to mutually exchanging the values of the variables. Usually, this is done with the data in <a href="/facts/Computer_storage/wPHKFpdx">memory</a>. For example, in a <a href="/facts/Computer_program/e38jH9N9">program</a>, two variables may be defined thus (in <a href="/facts/Pseudocode/XgN19duK">pseudocode</a>):

data_item x := 1
data_item y := 0

swap (x, y);
After swap() is performed, x will contain the value 0 and y will contain 1; their values have been exchanged. This operation may be generalized to other types of values, such as <a href="/facts/String_(computer_science)/4ChJu5WS">strings</a> and aggregated <a href="/facts/Data_type/fcx5hgVL">data types</a>. <a href="/facts/Comparison_sort/X1PvE50c">Comparison sorts</a> use swaps to change the positions of data.
In many <a href="/facts/Programming_language/cWTYbgWa">programming languages</a> the swap <a href="/facts/Subroutine/9vFJrg0A">function</a> is built-in. In <a href="/facts/C%252B%252B/Et0F2qn9">C++</a> <a href="/facts/Function_overloading/wL27p4rD">overloads</a> are provided allowing std::swap to exchange some large structures in O(1) time.

Swap (computer programming) open-in-new

Swap (computer programming)