Posts

Different Ways to Initialize an Array, and their Performance
Discuss minor performance issues introduced by array initialization in competitive programming.
Jul 06, 2020 8 min read
Educational Codeforces Round #89
Educational Codeforces Round #89 A. Shovels and Swords 问题重述 给你数 $a$ 和 $b$ ，求 $$\max x + y \quad \text{s. t.} x, y \in
Jun 12, 2020 4 min read
Codeforces Round #628 (Div. 2)
Codeforces Round #628 A. EhAb AnD gCd 问题重述 给你数 $x$，让你求 $a, b$ 使得 $GCD(a, b) + LCM(a, b)
Mar 15, 2020 3 min read
CodeCraft-20 (Div. 2)
CodeCraft-20 A. Grade Allocation 问题重述 给你 $n$ 个整数，让你修改一下它们，使得它们仍然
Mar 15, 2020 4 min read
A Guide to Undefined Behavior in C and C++
This is a Chinese translation of the original article on John Regehr’s blog.
Nov 13, 2019 23 min read
Time complexity problem
Another stupid problem can lead to some thoughts.
Sep 13, 2019 4 min read
Problem F, CF Round #536 (Div. 2)
Solution of Lunar New Year and a Recursive Sequence
Feb 02, 2019 2 min read
Analysis of Undefined Behaviors from an Examination
Even a stupid problem can lead to some thoughts.
Sep 06, 2018 10 min read
What Every C Programmer Should Know About Undefined Behavior #3/3
This is a Chinese translation of the original article on LLVM blog.
Sep 04, 2018 10 min read
What Every C Programmer Should Know About Undefined Behavior #2/3
This is a Chinese translation of the original article on LLVM blog.
Sep 04, 2018 8 min read