Practice · 3 of 3

A const rvalue cannot be moved from

CHALLENGE

Difficulty: advanced+25 XP

Implement std::string concat(const std::string& a, const std::string& b) returning the concatenation **by value**, and std::string sabotage(const std::string&& a, const std::string&& b) that must still produce a + b even though its parameters are const rvalues.

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