#include <iostream>
#include <vector>
 
void Concatenate( std::vector<char>& string1, std::vector<char> string2 ) {
	string1.insert( string1.end(), string2.begin(), string2.end() );
}
 
int main() {
	std::vector<char> firstString;
	firstString.push_back('A');
	firstString.push_back('B');
	std::vector<char> secondString;
	secondString.push_back('X');
	secondString.push_back('Y');
 
	Concatenate( firstString, secondString );
 
	for( auto it = firstString.begin(); it != firstString.end(); ++it )
	{
		std::cout << (*it);
	}
 
	return 0;
 
}

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