Difference between revisions of "ICL 2016 (GP of Tatarstan)"

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Solved by kblack. 02:56 (+3)
 
Solved by kblack. 02:56 (+3)
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题意:有个 $(a, b)$,可以操作成 $(a+1, b+1)$、$(\frac{a}{2},\frac{b}{2})$(要求整除),$(a, b)$ $(b, c)$可以搞成 $(a, c)$,都不是消耗品,让你把 $(a, b)$ 整成 $(c, d)$。
 +
 +
题解:注意到 $b-a$ 除了 2 以外的质因子都去不掉,可以操作的充要条件是 $(a == b && c == d) || ((a-b)*(c-d)>0 && (c-d)%(abs(a-b)>>__builtin_ctz(abs(a-b)) == 0)$,然后就随便搞一搞,注意造过的缓存一下,防止使用太多操作。
  
 
== Problem M ==
 
== Problem M ==

Revision as of 12:33, 3 March 2019

Problem A

Upsolved by ultmaster. (-2)

题意:给定三点 $A,B,C$,求一点 $Q$ 使得 $AQB = \alpha_1$, $BQC = \alpha_2$。

题解:搞出四个圆,然后两两配对。注意交点不能和给定点重合,注意圆重合的情况。

Problem B

Unsolved. (-10)

Problem C

Solved by ultmaster. 01:34 (+1)

题意:有 $n$ 个东西,每个东西已知一些事件发生,求在此条件下 另一系列事件发生的概率。

题解:条件概率公式。注意权重。

Problem D

Unsolved.

Problem E

Unsolved.

Problem F

Solved by ultmaster. 00:42 (+1)

题意:问有多少个有序数列满足 gcd 是 d,lcm 是 m。

题解:m /= d。然后简单容斥一下。

Problem G

Solved by zerol. 00:13 (+)

Problem H

Solved by zerol. 01:36 (+2)

Problem I

Solved by zerol. 00:49 (+)

Problem J

Solved by zerol. 03:21 (+2)

Problem K

Solved by kblack. 02:06 (+1)

Problem L

Solved by kblack. 02:56 (+3)

题意:有个 $(a, b)$,可以操作成 $(a+1, b+1)$、$(\frac{a}{2},\frac{b}{2})$(要求整除),$(a, b)$ $(b, c)$可以搞成 $(a, c)$,都不是消耗品,让你把 $(a, b)$ 整成 $(c, d)$。

题解:注意到 $b-a$ 除了 2 以外的质因子都去不掉,可以操作的充要条件是 $(a == b && c == d) || ((a-b)*(c-d)>0 && (c-d)%(abs(a-b)>>__builtin_ctz(abs(a-b)) == 0)$,然后就随便搞一搞,注意造过的缓存一下,防止使用太多操作。

Problem M

Solved by kblack. 00:07 (+)

温暖的签到。