• ## Orange Boy Can You Solve it Out? Ep. 28.5

思考题so late? Dazzit Again This is an easy version of OBCYSIO 28) You are given an integer sequence A of length N and another sequence B of length M. Then imagine a game: First, you choose exactly M different elements and arrange them, let's call ……
XGN 2020-02-06
• ## LSS 1 Editorial

Contest Link If you haven't read the problems or tried to solve it yourself, don't read this. A - Clock Difficulty: d2b Hint The hour hand of the clock moves 0.5 degree per minute, the minute hand of the clock moves 6 degree per minute. Then it tur……
XGN 2020-01-16
• ## [Indiscipline][0]神必的不等式

这是一个神必的不等式技巧,睡觉时候想的,我也不知道对不对,用就完事儿了 :/ 0.1 如图,这是一个严格上凸函数y=f(x) 它的上面有两点(x_0,y_0),(x_1,y_1) 先做出这两点的2条切线,再将这两点连起来 易观察得斜率由大到小分别是左边切线,中间连线,右边切线 证明亦不难: 由……
HDD 2020-01-14
• ## [Crimson Boy Can You Solve This?] [0] easy algebra

This is an easy algebra problem. I believe clever jgh must can solve it in 1min! We know that x-\frac{y}{z}-\frac{z}{y}=y-\frac{x}{z}-\frac{z}{x}=z-\frac{x}{y}-\frac{y}{x}=a and x {\neq}y{\neq}z (1) What is the value of x+y+z ? (2) What is the valu……
HDD 2020-01-05
• ## Orange Boy Can You Solve It Out? Ep. 35

思考题 for 2020 DuiLian 二十年飞花不尽 一几度落月无穷 九州同乐 Of twenty years, the flower never withers In one eternity, the moon forever remains Enjoy it together It's 2020 soon. It's time for the biggest holiday - The Yuandan and the Chinese Ne……
XGN 2019-12-31
• ## Orange Boy Can You Solve It Out? Ep. 34

思考题 about cheating Lottery Cheating Let's have some lottery! In this lottery system, a number string S and an array of integers A is predetermined. It is known that |A|=|S| and let's define A_0=0. Each user chooses a number string T(|T|=|S|). Th……
XGN 2019-12-10
• ## Orange Boy Can You Solve It Out? Ep. 33

思考题 Times A shadow pokemon! Recently the famous game Pokemon SwordString was released. XGN, one of the biggest fan of Pokemon, decided to have a try. In each battle, your Pokemon can be seen as a string A and the enemy can be seen as a string B.……
XGN 2019-12-09
• ## Orange Boy Can You Solve It Out? Ep. 32

思考题 in one sentence Yet Another Easy Problem Find any positive integer pair a,b so that (a+b)+(a+b)\mod k=n where k,n are given or -1 -1 if not found. Examples Input K=100 N=268 Output 200 34 Explain 200+34+(200+34)mod 100=234+34=268 Input K=100……
XGN 2019-12-04
• ## Orange Boy Can You Solve It Out? Ep. 31 (Hard)

If you prefer easier problem, please visit here 思考题 for dw Childish War (Hard) Miss. Broken Tail(Wei Duan) is the Math teacher of NFLS Class 8 Junior 3.She is a kind teacher. Miss. East(Fang Dong) is the Math teacher of NFLS Class 4 Junior 3.She……
XGN 2019-11-30
• ## Orange Boy Can You Solve It Out? Ep. 30 (Easy)

If you prefer harder problem, please visit here 思考题 for dw Childish War (Easy) Miss. Broken Tail(Wei Duan) is the Math teacher of NFLS Class 8 Junior 3.She is a kind teacher. Miss. East(Fang Dong) is the Math teacher of NFLS Class 4 Junior 3.She……
XGN 2019-11-30