Sorting is a fundamental operation in programming, and programming languages provide various ways to sort data. In C++, the std::sort function from the <algorithm> header is commonly used for sorting. By default, std::sort uses the < operator for comparison, which works well for numeric and string types. However, sorting custom types or user-defined literals often requires a custom comparison function or operator overloading.

In this blog post, we will explore how to perform custom sorting with custom literals in C++. We will demonstrate how to define a custom comparison function for sorting custom types and how to use it with std::sort.

Defining Custom Comparison Function

To perform custom sorting with custom literals, we first need to define a comparison function that specifies the desired sorting order. The comparison function should return true if the first argument should come before the second argument, and false otherwise.

Let’s say we have a custom type called Person with two properties: name and age. To sort a vector of Person objects in ascending order of their ages, we can define a comparison function as follows:

bool compareByAge(const Person& p1, const Person& p2) {
    return p1.age < p2.age;
}

In this example, the comparison function compares Person objects based on their age property.

Using Custom Comparison Function with std::sort

Now that we have our custom comparison function defined, we can use it with std::sort to sort our custom objects.

std::vector<Person> people = {{"John", 25}, {"Alice", 30}, {"Bob", 20}};

std::sort(people.begin(), people.end(), compareByAge);

In this example, we have a vector of Person objects, and we pass the compareByAge comparison function as the third argument to std::sort. This tells std::sort to use our custom comparison function for sorting the people vector.

The resulting vector will be sorted in ascending order of the age property.

Conclusion

Custom sorting with custom literals in C++ requires defining a custom comparison function and using it with std::sort. By leveraging custom comparison functions, we can sort custom types based on specific criteria.

By providing a way to customize the sorting behavior, C++ empowers programmers to sort data in a way that best suits their needs.

Remember to use meaningful comparison logic in your custom comparison functions for accurate and efficient sorting of custom types!