set-member – Set membership – Computer Science by Example

set-member – Set membership

Write a program that is able to print whether a number is element of a set of numbers.

2 ∈ {1,2,3} and 7 ∉ {1,2,3}

For example, the number two is an element of the set of numbers one, two and three. The number seven is not an element of the set of numbers one, two and three. In symbolic terms:

2 ∈ {1,2,3}
7 ∉ {1,2,3}

Input and output

Each line of input will contain either a set definition or a membership query. Each set definition begins with the word set followed by a list of numbers separated by a single space. Each membership query begins with the word member followed by a single number.

For each line of input there should be a line of output. For set definitions, your program should print using set {<a>,<b>,...,<z>} where numbers <a> through <z> are the members of the given set. For membership queries, your program should print whether the given number is a member of the last defined set with either:

<n> is an element of {<a>,<b>,...,<z>}
<n> is not an element of {<a>,<b>,...,<z>} where <n> is the number given on the input.

In the output, either give the elements in the same order given on the input or in ascending numeric order.

All input numbers will be in the range from 0 to 99 inclusive, i.e.: 0 ≤ x < 100. Input sets will not have repeated elements and may be empty. Input always begins with a set definition. Any leading zeroes on input numbers should be ignored.

Example input

set 1 2 3
member 2
member 7
set 3 5 7
member 2
member 7

Example output

using set {1,2,3}
2 is an element of {1,2,3}
7 is not an element of {1,2,3}
using set {3,5,7}
2 is not an element of {3,5,7}
7 is an element of {3,5,7}

Scoring

Performance is not in the scope of this exercise. Your program does not need to have optimal performance to get a full score. You can implement your solution in the simplest way possible.

1/6: works for the above example but produces output in an incorrect format
2/6: works for the above example and produces output in the correct format
5/6: works for other test cases
6/6: works for edge test cases

Hints

Since performance is not in the scope of this exercise feel free to use any simple data structure to represent sets. An array of booleans or a list of members should be enough to get a full score. You may use the fact that elements are restricted to the 0-99 range.

try first: bool-calc bool-not

try next: set-ui

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