#include <iostream>
    #include <string>
    #include <algorithm>
    #include <cwctype>
    #include <locale>
 
    int main()
    {
    	std::wstring wstr1 = L"dll", wstr2 = L"DLL";
 
    	auto icompare = [](wchar_t const &c1, wchar_t const &c2)
    	{ 
    		return std::tolower(c1, std::locale()) == std::tolower(c2, std::locale());
    	};
 
    	if (std::equal(wstr1.begin(), wstr1.end(), wstr2.begin(), wstr2.end(), icompare))
    		std::cout << "equal" << std::endl;
    	else
    		std::cout << "notEqual" << std::endl;
 
    	return 0;
    }
 

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