#include <iostream>
#include <iomanip>
#include <string>
 
int main()
{
	std::string a = "\\u00c1\\u00c4\\u00d3 dsfgdfg";
 
	std::wstring ws;
	ws.reserve(a.size());
 
	size_t start = 0;
	do
	{
		size_t found = a.find("\\u", start);
		if (found == std::string::npos) break;
 
		if (start < found)
			ws.insert(ws.end(), a.begin()+start, a.begin()+found);
 
		wchar_t wc = static_cast<wchar_t>(std::stoi(a.substr(found+2, 4), nullptr, 16));
		ws.push_back(wc);
 
		start = found + 6;
	}
	while (true);
 
	if (start < a.size())
		ws.insert(ws.end(), a.begin()+start, a.end());
 
	std::wcout << ws.size() << L" " << ws << std::endl;
	for(size_t i = 0; i < ws.size(); ++i) {
	    std::wcout << L"ws[" << i << L"] = " << std::hex << std::setw(4) << std::setfill(L'0') << static_cast<int>(ws[i]) << std::endl;
	}
 
	return 0;
}

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