Can anyone help me decipher this?

[Remixt]

Okay, so I've been learning C++ trying to catch up with my intermediate class. I just got my programming assignment for the week and I don't really understand what my professor is asking for and he hasn't answered my emails. I really have no idea where to even start.

 

Here is what he wants:

 

As "advertised", you are to complete and submit a C++ implementation of sets that use characteristic vector(s) to represent sets. What on gods green earth is a characteristic vector? Does anyone have an idea of how I can break this down and do it?

[ReesZRB]

First off bad place for programming advice. 

Take a look
http://stackoverflow.com/questions/5599642/how-to-do-the-vector-of-sets-in-c

[originalNam3]

has your tutor specified anything else other than as "advertised"

[Remixt]

Just now, originalNam3 said:

has your tutor specified anything else other than as "advertised"

Yeah there is an example program, 

 

#pragma once
using namespace std;
#include <iostream>
#include <assert.h>

class Set 
{
    public :

    Set();
    Set(const Set& s);    // copy constructor
    ~Set();
    void add(int i);
    void remove(int i);
    int size();
    int is_member(int i);
    void operator=(const Set& s);
    Set operator&(const Set& s);    // intersection
    Set operator|(const Set& s);    // union
    Set operator^(const Set& s);    // exclusive OR
    Set operator-(const Set& s);    // set difference

    void printSet();

    private:   // whatever you want to add, probably including any data 
               // associated with a Set, like maybe an array of unsigned ints
};
 

[originalNam3]

Uh okay...from this wiki link on sets (computer science): https://en.wikipedia.org/wiki/Set_(abstract_data_type) . I think, from what I'm understanding...you're supposed to make a program with a set range and when something inputted is within a some characteristic related to your vector/container you add that value to the vector. so you have a vector called odd; you input 3 into the program. 3 is an odd number so you add it to the odd vector and so on. But there cannot be repeats in your set so if 3 is inputted again you don't store both of them in odd you keep just one.

 

Though I could be entirely wrong and I'm sorry if i have confused you even further

[madknight3]

1 hour ago, Remixt said:

What on gods green earth is a characteristic vector?

Sorry if I'm incorrect but I think it's referring to this. Simple right? Well, I understand if that's also confusing so I'll try to explain it as I understand it.

 

Lets use an easy example (using pseudocode).

// Lets assume you're storing a set of boolean values
// The set of all boolean values is {False, True}
// So the characteristic vector would be
vec = [0,0]

// and here's your currently empty set
set = {}

// vec[0] denotes false
// vec[1] denotes true

// So if you have your own set object and you add false to it.
// Then you change the false location to 1
// Now you have
set = {false}
vec = [1,0]

// Now if you add true to your set you have
set = {false, true}
vec = [1,1]

// if you try to add true or false to your set, you know they already exist
// because the characteristic vector has a 1 in those spots

// Now if you remove false from your set you have
set = {true}
vec = [0,1]

 

Lets take something a little bigger but still easy.

// Lets assume you're storing a set of integer values in the range of 1 and 10 inclusive
// The set of all values is {1, 2, 3, 4, 5, 6, 7, 8, 9, 10}
// So the characteristic vector would be

vec = [0,0,0,0,0,0,0,0,0]

// vec[0] denotes 1
// vec[1] denotes 2
// etc

// and here's your currently empty set
set = {}

// So if you have your own set object and you add 5 to it.
// Then you change the 5th location to 1
// Now you have
set = {5}
vec = [0,0,0,0,1,0,0,0,0,0]

// if you try to add 5 to it again you know it already exists
// because the characteristic vector has a 1 in that spot

The same concept can be applied to ASCII characters, or anything that can be represented uniquely by a natural number. Hopefully you are getting the idea.

[Nineshadow]

He wants you to implement a set class/structure using characteristic/occurence vectors. It essentially counts the occurrences of values in another vector. Let's say you have a vector with the elements 0,2,1,4,3,2. You then create another vector with the size of the max element in the original vector(+1) . You iterate over the old vector and for each cell you will get a value t. You then make the value at the t index of the characteristic array 1. This means that at all times you will not have duplicates in a set ,and that elements can always be accessed in a specific order , ascending by default. And if you have an already sorted vector, you can more easily find elements in it. (I think it's O(logN) )

[Remixt]

On 2/8/2016 at 4:02 PM, madknight3 said:

Sorry if I'm incorrect but I think it's referring to this. Simple right? Well, I understand if that's also confusing so I'll try to explain it as I understand it.

 

Lets use an easy example (using pseudocode).

// Lets assume you're storing a set of boolean values
// The set of all boolean values is {False, True}
// So the characteristic vector would be
vec = [0,0]

// and here's your currently empty set
set = {}

// vec[0] denotes false
// vec[1] denotes true

// So if you have your own set object and you add false to it.
// Then you change the false location to 1
// Now you have
set = {false}
vec = [1,0]

// Now if you add true to your set you have
set = {false, true}
vec = [1,1]

// if you try to add true or false to your set, you know they already exist
// because the characteristic vector has a 1 in those spots

// Now if you remove false from your set you have
set = {true}
vec = [0,1]

 

Lets take something a little bigger but still easy.

// Lets assume you're storing a set of integer values in the range of 1 and 10 inclusive
// The set of all values is {1, 2, 3, 4, 5, 6, 7, 8, 9, 10}
// So the characteristic vector would be

vec = [0,0,0,0,0,0,0,0,0]

// vec[0] denotes 1
// vec[1] denotes 2
// etc

// and here's your currently empty set
set = {}

// So if you have your own set object and you add 5 to it.
// Then you change the 5th location to 1
// Now you have
set = {5}
vec = [0,0,0,0,1,0,0,0,0,0]

// if you try to add 5 to it again you know it already exists
// because the characteristic vector has a 1 in that spot

The same concept can be applied to ASCII characters, or anything that can be represented uniquely by a natural number. Hopefully you are getting the idea.

That makes things easier to understand. I at least have a starting point now. Thank you