How to create a Set of Sets in C++ - Step by Step Examples

How to create a Set of Sets in C++ ?

Answer

To create a Set of Sets in C++, you can use nested std::unordered_set containers. You create individual sets using std::unordered_set and then add them to another std::unordered_set.

✐ Examples

1 Creating a Set of Sets of Integers

In this example,

First, we include the necessary header file <unordered_set>.
Next, we create three individual sets of integers named set1, set2, and set3 using std::unordered_set. We insert the elements 1, 2, 3 into set1, 4, 5, 6 into set2, and 7, 8, 9 into set3.
Then, we create a set of sets named setOfSets using std::unordered_set, and we insert set1, set2, and set3 into setOfSets. This nests the three sets within a single set.
Finally, we iterate over each set within setOfSets using a range-based for loop. Within the loop, we print each individual set to the standard output.

C++ Program

#include <iostream>
#include <unordered_set>

int main() {
    std::unordered_set<int> set1 = {1, 2, 3};
    std::unordered_set<int> set2 = {4, 5, 6};
    std::unordered_set<int> set3 = {7, 8, 9};

    std::unordered_set<std::unordered_set<int>> setOfSets = {set1, set2, set3};

    for (const auto& set : setOfSets) {
        for (const auto& element : set) {
            std::cout << element << " ";
        }
        std::cout << std::endl;
    }
    return 0;
}

Output

Output:
1 2 3
4 5 6
7 8 9

2 Creating a Set of Sets of Strings

In this example,

First, we include the necessary header file <unordered_set>.
Next, we create three individual sets of strings named setA, setB, and setC using std::unordered_set. We insert the strings "apple", "banana", "cherry" into setA, "dog", "elephant", "fox" into setB, and "grape", "honeydew", "kiwi" into setC.
Then, we create a set of sets named setOfStringSets using std::unordered_set, and we insert setA, setB, and setC into setOfStringSets. This nests the three sets within a single set.
Finally, we iterate over each set within setOfStringSets using a range-based for loop. Within the loop, we print each individual set to the standard output.

C++ Program

#include <iostream>
#include <unordered_set>
#include <string>

int main() {
    std::unordered_set<std::string> setA = {"apple", "banana", "cherry"};
    std::unordered_set<std::string> setB = {"dog", "elephant", "fox"};
    std::unordered_set<std::string> setC = {"grape", "honeydew", "kiwi"};

    std::unordered_set<std::unordered_set<std::string>> setOfStringSets = {setA, setB, setC};

    for (const auto& set : setOfStringSets) {
        for (const auto& element : set) {
            std::cout << element << " ";
        }
        std::cout << std::endl;
    }
    return 0;
}

Output

Output:
apple cherry banana
fox dog elephant
honeydew grape kiwi

Summary

In this tutorial, we learned How to create a Set of Sets in C++ language with well detailed examples.

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How to create a Set of Sets in C++ - Step by Step Examples

How to create a Set of Sets in C++ ?

Answer

✐ Examples

1 Creating a Set of Sets of Integers

C++ Program

Output

2 Creating a Set of Sets of Strings

C++ Program

Output

Summary

More C++ Sets Tutorials