#include <iostream>
#include <string>
 
static std::string ReplaceAll(std::string result, const std::string& src, const std::string& dest)
{
	size_t pos = 0;
 
	if (src == dest)
		return result;
 
	while ((pos = result.find(src, pos)) != std::string::npos)
	{
		result.replace(pos, src.size(), dest);
		pos += dest.length();
	}
 
	return result;
}
 
int main()
{
	std::cout << ReplaceAll("tetestst", "test", "") << std::endl;
	std::cout << ReplaceAll("  something   with   many spaces  ", "  ", " ") << std::endl;
 
	return 0;
}

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