How to check if a Set is Empty in C++

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How to check if a Set is Empty in C++ ?

Answer

To check if a Set is empty in C++, you can use the empty method or compare the size to zero.

✐ Examples

1 Check if Set is Empty Using empty Method

In this example,

We define a set named `mySet` containing elements of a specific type.
We use the `empty` method to check if the set is empty.
If the `empty` method returns `true`, then the set is empty; otherwise, it contains elements.

C++ Program

#include <iostream>
#include <set>

int main() {
    // Define set
    std::set<int> mySet;

    // Check if set is empty using empty method
    if (mySet.empty()) {
        std::cout << "Set is empty" << std::endl;
    } else {
        std::cout << "Set is not empty" << std::endl;
    }
    return 0;
}

Output

Set is empty

2 Check if Set is Empty Using size Method

In this example,

We define a set named `mySet` containing elements of a specific type.
We use the `size` method to get the number of elements in the set.
If the size is equal to zero, then the set is empty; otherwise, it contains elements.

C++ Program

#include <iostream>
#include <set>

int main() {
    // Define set
    std::set<int> mySet;

    // Check if set is empty using size method
    if (mySet.size() == 0) {
        std::cout << "Set is empty" << std::endl;
    } else {
        std::cout << "Set is not empty" << std::endl;
    }
    return 0;
}

Output

Set is empty

Summary

In this tutorial, we learned How to check if a Set is Empty in C++ language with well detailed examples.

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How to check if a Set is Empty in C++

How to check if a Set is Empty in C++ ?

Answer

✐ Examples

1 Check if Set is Empty Using empty Method

C++ Program

Output

2 Check if Set is Empty Using size Method

C++ Program

Output

Summary

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