find(2) lower_bound 和 upper_bound 函数 • find(x) 是找第一个等于 x 的元素。 • lower_bound(x) 找第一个大于等于 x 的元素 。 • upper_bound(x) 找第一个大于 x 的元素。 • 他们找不到时都会返回 end() 。 • find 的条件更加严格（必须相等才算找 到）， lower_bound 和 upper_bound 宽松。 • 所以如果集合中没有 2 ： • lower_bound(2) 会返回指向 3 的迭代器。 • upper_bound(2) 也会返回指向 3 的迭代器。 • find(2) 会直呼“找不到”然后返回 end() 了。 • iterator find(int const &val) const; • iterator lower_bound(int const &val) const; const &val) const; 0 1 3 4 5 upper_bound(2) begin() end() lower_bound(2) lower_bound 和 upper_bound 函数 • find(x) 是找第一个等于 x 的元素。 • lower_bound(x) 找第一个大于等于 x 的元素 。 • upper_bound(x) 找第一个大于 x 的元素。 • 他们找不到时都会返回

containers” 32 Source: ChatGPTUsing std::vector 33 • Using two vectors (bids and asks) and use std::lower_bound (binary search) std::vector> mBidLevels; std::vector> mAskLevels;Using std::vector 34 • Using two vectors (bids and asks) and use std::lower_bound (binary search) • AddOrder: - log(N) if the price level exists - log(N) + N if a new price level Compare> void AddOrder(T& levels, Price price, Volume volume, Compare comp) { auto it = std::lower_bound(levels.begin(), levels.end(), price, [comp](const auto& p, Price price) { return comp(p.first

Back to Basics: Classic STL Copyright © 2021 Bob Steagall Algorithms - Declaration of lower_bound • lower_bound • Action: Returns an iterator pointing to the first element in the range [first, last) the number of iterator increments is linear 70 template ForwardIt lower_bound(ForwardIter first, ForwardIter last, const T& value);CppCon 2021 – Back to Basics: Classic STL

} return right; }int BinSearch(int x, const int *a, int n) { return std::lower_bound(a, a + n, x) – a; }std::lower_bound(a, a + n, x)The source of the problem on the Yorktown was that bad data was

• Arrays are maximally space-efficient, very time-efficient • Sorted arrays: binary_search, lower_bound, equal_range • Now you can use constexpr algorithms • Easy: static_assert with constexpr is_sorted

• Arrays are maximally space-efficient, very time-efficient • Sorted arrays: binary_search, lower_bound, equal_range • Now you can use constexpr algorithms • Easy: static_assert with constexpr is_sorted

entries[0].input, entries[NUM_ENTRIES-1].input); auto entry_itr = std::lower_bound( entries.begin(), entries.end(), clamped_in, [](auto const &e, auto const &v)

design FlatMap Slower O(logn) lookup No per-cell overhead Easier to gather adjacent cells - lower_bound & upper_bound Types of queries impact which to pick Small area queries - fit within cell - HashMap

e 2 template < typename Policy , typename Iter , typename Comp > 3 __host__ __device__ Iter lower_bound( /* ... */ ); � � Not recommended42/66 Motivation Patterns The dark path Cuda proposal Thank

匹配多个字符。参数必须要匹配完整的字符串。通常，把%放在 字符串的尾部更加符合实际用法。 举例： expression BETWEEN lower_bound AND upper_bound expression BETWEEN lower_bound AND upper_bound mysql> select c1 from t1 where month between 1 and 6;