Иногда собеседования в IT-компаниях становятся настоящими испытаниями, требующими не только знаний, но и логического мышления и умения быстро принимать решения. Давайте об этом сегодня поговорим подробнее.
Бинарный поиск на языке Go
Этим постом начинаю тему алгоритмов на языке Go. Алгоритмы касаются не только айтишников, программирования и всяких там «странных» гиков. Они повсюду вокруг нас. Это основа. Для начала, определимся с тем, что же такое этот алгоритм.
LeetCode, Hard, last two problems: 2809. Min Time to Make Array Sum At Most x & 2813. Max Elegance of a K-Length Subseq
2813. Max Elegance of K-Length Subseq: Swift code for elegantly selecting unique k-length subsequences with profit and categories. Solution uses sorting and iteration. Time: O(nlogn), Space: O(n).
LeetCode 2532 (Hard++, Extra Category, Amazon). Time to Cross a Bridge. Swift
Overflow checks have been taken into consideration. The maximum time to move a box is at most 4 * 1000 (four steps to move the box, each taking 1000 time). With at most 1e4 boxes, the total time is at most 4e7, ensuring the solution is safe.
LeetCode 2801 (Hard, Acceptance Level 14.5%). Count Stepping Numbers in Range. DP. Handles large inputs (10^9 + 7)
The Swift solution uses dynamic programming to solve the problem. The rec function recursively calculates the count of stepping numbers based on certain conditions. The dp array is used to store previously computed results, which helps avoid redundant calculations and improves efficiency.
LeetCode 2790 (Hard). Maximum Number of Groups With Increasing Length. Solution of the day. O(N logN). Math
The time complexity of this solution is dominated by the sorting step, making it O(N logN), where N is the length of the input array usageLimits. The rest of the operations involve simple arithmetic and comparisons, which take linear time. Therefore, the overall time complexity of the function is O(N logN).
LeetCode 2612 (Hard). Minimum Reverse Operations. Swift. BFS. O(n+k). O(n)
The algorithm follows a breadth-first search (BFS) approach to determine the minimum number of reverse operations needed to bring the 1 to each position in the array.