Implement the Searcher class's BinarySearch$()$ template function in the Searcher.h file. Access Searcher.h by clicking on the orange arrow next to main.cpp at the top of the coding window. The function performs a binary search on the sorted array $($first parameter$)$ for the key $($third parameter$).$ BinarySearch$()$ returns the key's index if found, $-1$ if not found.