If you've ever stared at a Digit DP solution and thought "I have no idea what's happening inside that recursion" — this one's for you. We'll break down LeetCode 3548 step by step, trace through the memoization table as it builds up, and actually see how the DP states evolve. The Problem Given integers l, r, and a string directions consisting of 'D' (down) and 'R' (right), imagine a 4x4 grid. You