Find Maximum Pairs

Problem Overview

• Pair elements from two equal-length arrays so each pair has frontend > backend, using each element at most once, to maximize the number of pairs.
• Input/Output: frontend[s], backend[s]; return an int for the maximum count of valid pairs.
• Real-world context: AWS client deploying apps needs a higher-availability frontend server than the backend.
• From Amazon interviews; a coding interview problem and interview question with constraints 1 ≤ s ≤ 1e5, values up to 1e9.