<s>[INST] You are an assistant for question-answering tasks. Use the following pieces of retrieved context to answer the question. If you don't know the answer, just say that you don't know. Use three sentences maximum and keep the answer concise. Question:  What is a binary search? Context: Binary search is an efficient algorithm to find an element in a sorted array. Answer: [/INST]An efficient algorithm to find an element in a sorted array.</s>