673. 最长递增子序列的个数
Medium | Array, Dynamic Programming, Binary Indexed Tree, Segment Tree
Binary Indexed Tree
327. 区间和的个数
Hard | Array, Binary Search, Divide and Conquer, Binary Indexed Tree, Segment Tree, Merge Sort, Ordered Set
218. 天际线问题
Hard | Array, Divide and Conquer, Binary Indexed Tree, Segment Tree, Sweep Line, Sorting, Heap (Priority Queue), Ordered Set
307. 区域和检索 - 数组可修改
Medium | Array, Divide and Conquer, Design, Binary Indexed Tree, Segment Tree
315. 计算右侧小于当前元素的个数
Hard | Array, Binary Search, Divide and Conquer, Binary Indexed Tree, Segment Tree, Merge Sort, Ordered Set