General problem

1. Write set difference by C++ STL; assume sets = A - B, put result in set C.

 
        std::set_difference(A.begin(), A.end(), B.begin(), B.end(), 
            std::inserter(C, C.begin()));

留言

張貼留言

這個網誌中的熱門文章

https://leetcode.com/contest/weekly-contest-73/problems/rotated-digits/

slow: class Solution { public: int rotatedDigits(int N) { int total = 0; for (int i = 1; i <= N; i++) { int digit; int r = 0; int base = 1; int now = i; while (now) { digit = now % 10; now /= 10; if (digit == 0 || digit == 1 || digit == 8) r += (digit * base); else if (digit == 2) r += 5 * base; else if (digit == 5) r += 2 * base; else if (digit == 6) r += 9 * base; else if (digit == 9) r += 6 * base; else { r = i; break; } base *= 10; } if (r != i) { //printf("* %d %d\n", r, i); total++; } } ...
閱讀完整內容

shared pipe hlxSweExam

#include <cstdlib> #include <new> template <class T> struct Mallocator { typedef T value_type; Mallocator() = default; template <class U> constexpr Mallocator(const Mallocator<U>&) noexcept {} [[nodiscard]] T* allocate(std::size_t n) { if(n > std::size_t(-1) / sizeof(T)) throw std::bad_alloc(); if(auto p = static_cast<T*>(std::malloc(n*sizeof(T)))) return p; throw std::bad_alloc(); } void deallocate(T* p, std::size_t) noexcept { std::free(p); } }; template <class T, class U> bool operator==(const Mallocator<T>&, const Mallocator<U>&) { return true; } template <class T, class U> bool operator!=(const Mallocator<T>&, const Mallocator<U>&) { return false; } https://elloop.github.io/c++/2016-09-19/stl-apply-imp-95-simple-allocator http://www.cnblogs.com/suzhou/p/5381738.html http://www.justskins.com/forums/shm_open-vs-open-253314.html http://www.drdobbs.com/creati...
閱讀完整內容