LeetCode

LeetCode 812 note: with at most 50 points, enumerate every triple and take the largest shoelace area

LeetCode 806 note: simulate writing, wrapping when the next letter would exceed 100; landing exactly on 100 stays on the line

LeetCode 804 note: translate each word into a Morse string and count the distinct results with a set

LeetCode 796 note: goal is a rotation of s exactly when the lengths match and goal occurs in s + s

LeetCode 783 note: a BST’s in-order is ascending, so the minimum difference is between in-order neighbors; remember the previous value and compare

LeetCode 771 note: put jewels in a set and count how many stones are in it

LeetCode 766 note: every diagonal is constant exactly when each cell equals its upper-left neighbor

LeetCode 762 note: numbers are below 10^6 < 2^20, so the set-bit count is at most 19; check it against a small set of primes

LeetCode 748 note: count the plate’s letters in lowercase, then find the shortest word covering every count, taking the earliest on ties

LeetCode 747 note: find the largest and second largest in one pass and return the largest’s index if it is at least twice the second; multiply to avoid dividing by zero

LeetCode 744 note: find the first letter > target (an upper bound), wrapping around to the first letter if none exists

LeetCode 733 note: DFS or BFS from the start, recoloring 4-directional cells that share the start’s original color; return immediately if the colors are equal