int compare(const wstring& str) const;
#includeIn the above example, we are comparing two `wstring` objects `str1` and `str2` using the `compare` function. We are then checking the return value of the function and printing the appropriate message based on the comparison result. Package Library: The C++ `wstring` class is defined in the C++ standard library. Therefore, you do not need to install any external package or library to use the `compare` function.#include using namespace std; int main() { wstring str1 = L"Hello, world!"; wstring str2 = L"hello, world!"; int result = str1.compare(str2); if (result == 0) { cout << "Both Strings are equal" << endl; } else if (result > 0) { cout << "str1 is greater than str2" << endl; } else { cout << "str1 is less than str2" << endl; } return 0; }