byu_rself

LC.P1206[设计跳表] 方法一：构造123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110class Skiplist { private static final int MAX_LEVEL = 32; private static final double SKIPLIST_P = 0.25; private Node head; private int curLevel; public Skiplist() { this.head = new Node(-1, MAX_LEVEL); this.curLevel = ...

LC.P84[柱状图中最大的矩形] 方法一：单调栈12345678910111213141516171819202122232425class Solution { public int largestRectangleArea(int[] heights) { int n = heights.length, ans = 0; int[] l = new int[n], r = new int[n]; Arrays.fill(l, -1); Arrays.fill(r, n); Deque<Integer> stack = new ArrayDeque<>(); // 确定右边界 for (int i = 0; i < n; i++) { while (!stack.isEmpty() && heights[stack.peek()] > heights[i]) r[stack.p ...

LC.P239[滑动窗口最大值] 方法一：滑动窗口1234567891011121314151617181920212223class Solution { public int[] maxSlidingWindow(int[] nums, int k) { if (nums == null || nums.length < 2) return nums; Deque<Integer> queue = new ArrayDeque<>(); int n = nums.length; int[] ans = new int[n - k + 1]; for (int i = 0; i < n; ++i) { // 队列内从大到小 while (!queue.isEmpty() && nums[queue.peekLast()] <= nums[i]) { ...

LC.P726[原子的数量] 方法一：数据结构模拟12345678910111213141516171819202122232425262728293031323334353637383940414243444546474849505152535455565758596061626364656667686970717273747576777879808182838485868788class Solution { public String countOfAtoms(String formula) { int n = formula.length(); char[] s = formula.toCharArray(); Map<String, Integer> map = new HashMap<>(); Deque<String> stack = new ArrayDeque<>(); int i = 0, index = 0; ...

LC.P1079[活字印刷] 方法一：计数+回溯1234567891011121314151617181920212223class Solution { int[] cnt = new int[26]; public int numTilePossibilities(String tiles) { for (char c : tiles.toCharArray()) { ++cnt[c - 'A']; } return dfs(); } private int dfs() { int ans = 0; for (int i = 0; i < cnt.length; ++i) { if (cnt[i] > 0) { ++ans; --cnt[i]; a ...

LC.P1190[反转每对括号间的子串] 方法一：栈123456789101112131415161718192021class Solution { public String reverseParentheses(String s) { Deque<Character> stack = new ArrayDeque<>(); for (int i = 0; i < s.length(); ++i) { char c = s.charAt(i); if (c == ')') { List<Character> list = new ArrayList<>(); while (stack.peek() != '(') list.add(stack.pop()); stack.pop(); ...

LC.P1073[负二进制数相加] 方法一：模拟12345678910111213141516171819202122232425262728293031class Solution { public int[] addNegabinary(int[] arr1, int[] arr2) { List<Integer> list = new ArrayList<>(); for (int i = arr1.length - 1, j = arr2.length - 1, c = 0; i >= 0 || j >= 0 || c != 0; --i, --j) { int x = c; if (i >= 0) x += arr1[i]; if (j >= 0) x += arr2[j]; if (x >= 2) { // 逢二进负一 x -= 2 ...

在SpringBoot项目本地调试过程中，若有不需要的自启动方法，则会捣乱输出大堆日志、修改数据等。以下是总结的SpringBoot项目的常见自定动方式： @Scheduled(fixedRate = 5 * 60 * 100)定时的cron时间特别短 继承CommandLineRunner或ApplicationRunner的类的run方法 被@EventListener注解的方法参数是ApplicationReadyEvent implements ApplicationListener<ContextRefreshedEvent>的类的onApplicationEvent(ContextRefreshedEvent event) @PostConstruct 类初始化后执行操作，但是不能保证Spring容器已完全初始化，ApplicationContextAware不保证能取到值，最好用ApplicationRunner或者@EventListener while(true) 空构造器里的持续执行 搜索 Quartz，JobDetailFactoryBean，Cro ...

LC.P622[设计循环队列] 方法一：双指针123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354class MyCircularQueue { int[] data; int size, head, tail; public MyCircularQueue(int k) { data = new int[k]; size = 0; head = 0; tail = k - 1; } public boolean enQueue(int value) { if (isFull()) return false; tail = tail == data.length - 1 ? 0 : tail + 1; data[tail] = value; ++size; ...

LC.P2446[判断两个事件是否存在冲突] 方法一：模拟123456class Solution { public boolean haveConflict(String[] event1, String[] event2) { // event1的开始时间大于event2的结束时间或者event1的结束时间小于event2的开始时间则没有冲突 return !(event1[0].compareTo(event2[1]) > 0 || event1[1].compareTo(event2[0]) < 0); }} 时间复杂度：$O(1)$ 空间复杂度：$O(1)$