CISC 102 Lecture 5: Indexed Sets

• School: Queen's University
• Department: Computing
• Course: CISC 102
• Professor: David Rappaport

Document Summary

A partition of s consists of disjoint non-empty subsets of s whose union is s. Let s be the set {1, 2, 3, 4, 5, 6}: E o = and e o = s, so the set (of sets) {e,o} is a partition of s. Another partition of s could be ({1, 2}, {3, 4, 5}, {6}) Splitting a set into a partition can sometimes be useful for solving algorithmic problems. You can then solve each set of the partition in cases. A collection, or class of sets can be defined using an index as follows: Let (cid:3036) denote the set {x : x z , x i}, for all i n. A1 = { 1, 2, 3, }, a2 = { 2, 3, 4, }, a3 = { 3, 4, 5, } Shorthand can be used to denote multiple unions and intersection operations.