LeetCode

LeetCode 522 note: the longest uncommon subsequence is always a whole string; check strings from longest to shortest, and the first that is not a subsequence of any other long-enough string is the answer

LeetCode 1826 note: at the first mismatch, test both “who dropped a value” explanations; if both fit, it cannot be determined, so return -1

LeetCode 3885 note: a dict of current priorities plus a max-heap with lazy deletion, validated on pop

LeetCode 3884 note: compare from both ends toward the middle; the first match is the answer, and odd lengths always match in the middle

LeetCode 1023 note: two pointers character by character; anything beyond the pattern must be lowercase

LeetCode 3843 note: count each value, then count how many values share each count; the first element from the left whose count is its own is the answer

LeetCode 3842 note: toggle membership in a set, or keep bulbs appearing an odd number of times, then sort

LeetCode 3840 note: houses conflict only when adjacent with the same color; take a house outright when the colors differ, and do the House Robber choice only when they match

LeetCode 3839 note: words sharing the first k characters are connected, so count by word[:k]; exclude words shorter than k

LeetCode 3838 note: sum each word’s letter weights mod 26 and map backward: 0 -> z, i.e. chr(ord(‘z’) - r)

LeetCode 3719 note: n is only 1500, so fix the left end and extend right, maintaining distinct odds and evens in two sets

LeetCode 2838 note: sort monsters by power, build coin prefix sums, and bisect_right per hero