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| | Transitive Closure |
 | | For example, Fosco Baggins is the father of Drogo, and Drogo is the father of Frodo; therefore, Fosco is an ancestor of Frodo by transitivity. |
 | | More formally, transitive closure is an extension or superset of a binary relation such that whenever (a,b) and (b,c) are in the extension, (a,c) is also in the extension. |
 | | For example, the transitive closure of a BOM input is all pairs of containing/contained items, be they contained directlye.g., if a cake contains cream, return (cake, cream)or indirectlye.g., if a cake contains cream and cream contains sugar, a cake transitively contains sugar; return (cake, cream), (cream, sugar), (cake, sugar). |
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