Array

LeetCode 1122 note: count first, emit values in arr2’s order, then append the remaining values in ascending order

LeetCode 1089 note: count the zeros to know each value’s shift, then move from back to front, writing the extra 0 when copying a zero

LeetCode 1051 note: sort and count the positions that differ from the original

LeetCode 1046 note: from a max-heap (negated values) take the two heaviest each round, push back their difference if unequal, and return the last stone or 0

LeetCode 1030 note: list every coordinate and sort by Manhattan distance to the center; return coordinates, not distances

LeetCode 997 note: the judge is trusted by the other n - 1 people and trusts nobody, so in-degree minus out-degree equals n - 1

LeetCode 1018 note: each new bit turns the prefix into x = 2x + bit, so keep only x mod 5 and the number never grows

LeetCode 1013 note: the total must be divisible by 3; accumulate from the left, cutting whenever the running sum hits total / 3, and succeed with at least 3 pieces

LeetCode 1005 note: negate the smallest value each time; once the smallest is positive, only the parity of the remaining count matters

LeetCode 1002 note: count each word and intersect all Counters (minimum count per character), then expand

LeetCode 989 note: treat k as the carry, add from the last element backwards, and keep prepending digits while k remains

LeetCode 977 note: the largest squares are at the two ends, so compare the ends with two pointers and fill the result from the back