From d92be769b7725c869e4c59b9d8fa4afaebe55aed Mon Sep 17 00:00:00 2001
From: ken <1598584570@qq.com>
Date: Sun, 19 Oct 2025 20:25:09 +0800
Subject: [PATCH 1/2] =?UTF-8?q?Add=20problem:=20K=E8=BF=9B=E5=88=B6?=
 =?UTF-8?q?=E5=90=8E=E7=BD=AE=E9=9B=B6=E4=B8=AA=E6=95=B0?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 exercise1.md | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)
 create mode 100644 exercise1.md

diff --git a/exercise1.md b/exercise1.md
new file mode 100644
index 0000000..e9efb2d
--- /dev/null
+++ b/exercise1.md
@@ -0,0 +1,21 @@
+# 题目：K进制后置零个数
+
+花生可很讨厌数学，尤其是各种奇奇怪怪的定义。  
+导师让花生可去找一串实验数据的中位数，花生可大声叫“就你是中位数，实验数据有问题就删你”，  
+结果不小心被导师听到了，导师默默说出“就你不喜欢中位数是吧，实验数据有问题就练你”。
+
+计算机拿二进制存数据，但是有的时候会有很多后置零，如2^31就有31个0。  
+导师想把后置零单独存储以缩减内存，同时为了未来三进制、四进制电脑的兼容性，导师要求你在 **K进制下求 n 的后置零个数**。
+
+## 输入描述
+一行两个整数 `n k`，表示计算 n 的 K 进制表示末尾零的个数。  
+- 1 ≤ n ≤ 10^12  
+- 2 ≤ k ≤ 10  
+
+## 输出描述
+输出一个整数，表示 n 在 K 进制下的末尾零个数。
+
+## 样例输入 
+8 2
+## 样例输出
+3
\ No newline at end of file

From b71d50db5a33370d410c4b348fe2d863496f77df Mon Sep 17 00:00:00 2001
From: ken <1598584570@qq.com>
Date: Wed, 22 Oct 2025 20:49:51 +0800
Subject: [PATCH 2/2] Add new problem solutions for week 1

---
 week1-exercise1 .in | 235 ++++++++++++++++++++++++++++++++++++++++++++
 week1-exercise1 .md |  32 ++++++
 week1-exercise1.out | Bin 0 -> 18944 bytes
 week1-exercise2.in  |  71 +++++++++++++
 week1-exercise2.md  |  56 +++++++++++
 week1-exercise2.out |  10 ++
 week1-exercise3.in  |  10 ++
 week1-exercise3.md  |  48 +++++++++
 week1-exercise3.out |  10 ++
 9 files changed, 472 insertions(+)
 create mode 100644 week1-exercise1 .in
 create mode 100644 week1-exercise1 .md
 create mode 100644 week1-exercise1.out
 create mode 100644 week1-exercise2.in
 create mode 100644 week1-exercise2.md
 create mode 100644 week1-exercise2.out
 create mode 100644 week1-exercise3.in
 create mode 100644 week1-exercise3.md
 create mode 100644 week1-exercise3.out

diff --git a/week1-exercise1 .in b/week1-exercise1 .in
new file mode 100644
index 0000000..1a5650b
--- /dev/null
+++ b/week1-exercise1 .in	
@@ -0,0 +1,235 @@
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diff --git a/week1-exercise1 .md b/week1-exercise1 .md
new file mode 100644
index 0000000..41c40b1
--- /dev/null
+++ b/week1-exercise1 .md	
@@ -0,0 +1,32 @@
+# K
+
+## 题目描述
+
+现有 $n$ 个正整数，要求出这 $n$ 个正整数中的第 $k$ 个最小整数（相同大小的整数只计算一次）。
+
+## 输入格式
+
+第一行为 $n$ 和 $k$; 第二行开始为 $n$ 个正整数的值，整数间用空格隔开。
+
+## 输出格式
+
+第$k$个最小整数的值；若无解，则输出 `NO RESULT`。
+
+## 输入输出样例 #1
+
+### 输入 #1
+
+```
+10 3
+1 3 3 7 2 5 1 2 4 6
+```
+
+### 输出 #1
+
+```
+3
+```
+
+## 说明/提示
+
+$n \leq 10000$，$k \leq 4000$，正整数均小于 $30000$。
diff --git a/week1-exercise1.out b/week1-exercise1.out
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HcmV?d00001

diff --git a/week1-exercise2.in b/week1-exercise2.in
new file mode 100644
index 0000000..2828524
--- /dev/null
+++ b/week1-exercise2.in
@@ -0,0 +1,71 @@
+"3
+336366944
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+"5
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+"3
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+"8
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+19195"
+"10
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diff --git a/week1-exercise2.md b/week1-exercise2.md
new file mode 100644
index 0000000..7dbe30e
--- /dev/null
+++ b/week1-exercise2.md
@@ -0,0 +1,56 @@
+# GCD? GCD!
+
+## 题目描述
+
+awk喜欢 $\mathrm{gcd}$，也就是 **最大公约数**。如果你不知道什么叫做最大公约数，你可以访问 [最大公约数 - OI Wiki](https://oi-wiki.org/math/gcd/)。
+
+awk给了你一个正整数 $n$，要你把它分成三个 **互不相等的** 正整数 $a,b,c$ 之和，使得 $\mathrm{gcd}(a,b,c)$ 最大。
+
+## 输入格式
+
+**本题有多组数据**。
+
+第一行一个正整数 $T$，表示数据组数。
+
+接下来 $T$ 行，每行一个正整数 $n$。
+
+## 输出格式
+
+对于每组数据，一行一个整数，表示答案，即最大的 $\mathrm{gcd}(a,b,c)$ 。 
+
+特别地，如果 $n$ 无法分成三个互不相等的正整数之和，请输出 `-1`。
+
+## 输入输出样例 #1
+
+### 输入 #1
+
+```
+3
+12
+27
+5
+```
+
+### 输出 #1
+
+```
+2
+3
+-1
+```
+
+## 说明/提示
+
+【样例解释】
+
+将 $12$ 分成 $2+4+6$，可以证明 $\gcd(2,4,6)=2$ 为可能达到的最大值。
+
+将 $27$ 分成 $3+6+18$，可以证明 $\gcd(3,6,18)=3$ 为可能达到的最大值。
+
+$5$ 无法分成三个互不相等的正整数之和，输出 `-1`。
+
+---
+
+【数据范围】
+
+对于 $100\%$ 的数据，$1\le T \le 100$，$1\le n\le 10^9$。
\ No newline at end of file
diff --git a/week1-exercise2.out b/week1-exercise2.out
new file mode 100644
index 0000000..9d73fab
--- /dev/null
+++ b/week1-exercise2.out
@@ -0,0 +1,10 @@
+42045868 4282444 8032754
+2 -1 1 1 9
+116 49 1379 4 2 1317 1660 3 1522 239
+1462465 7804 103811 1152217 872979 13168959
+4484897 1142001 27579125
+1451 4 421 197 2 1825 4980 1745
+1715 3 3 181 2686 1 1 1 2 866
+1514 1999 55167 4 23683 28738 2908
+8434 193 1 2015 17774 3
+843406 1 15172
diff --git a/week1-exercise3.in b/week1-exercise3.in
new file mode 100644
index 0000000..d233bb4
--- /dev/null
+++ b/week1-exercise3.in
@@ -0,0 +1,10 @@
+0-670-82162-4
+0-670-82552-3
+9-670-82552-3
+0-445-82599-3
+0-445-81120-3
+0-445-81120-X
+9-670-87777-6
+9-670-87757-4
+9-222-87757-4
+9-222-11101-4
diff --git a/week1-exercise3.md b/week1-exercise3.md
new file mode 100644
index 0000000..ca8c1ab
--- /dev/null
+++ b/week1-exercise3.md
@@ -0,0 +1,48 @@
+# 识别码吗
+
+## 题目描述
+
+每一本正式出版的图书都有一个 ISBN 号码与之对应，ISBN 码包括 $9$ 位数字、$1$ 位识别码和 $3$ 位分隔符，其规定格式如 `x-xxx-xxxxx-x`，其中符号 `-` 就是分隔符（键盘上的减号），最后一位是识别码，例如 `0-670-82162-4`就是一个标准的 ISBN 码。ISBN 码的首位数字表示书籍的出版语言，例如 $0$ 代表英语；第一个分隔符 `-` 之后的三位数字代表出版社，例如 $670$ 代表维京出版社；第二个分隔符后的五位数字代表该书在该出版社的编号；最后一位为识别码。
+
+识别码的计算方法如下：
+
+首位数字乘以 $1$ 加上次位数字乘以 $2$ ……以此类推，用所得的结果 $ \bmod 11$，所得的余数即为识别码，如果余数为 $10$，则识别码为大写字母 $X$。例如 ISBN 号码 `0-670-82162-4` 中的识别码 $4$ 是这样得到的：对 `067082162` 这 $9$ 个数字，从左至右，分别乘以 $1,2,\dots,9$ 再求和，即 $0\times 1+6\times 2+……+2\times 9=158$，然后取 $158 \bmod 11$ 的结果 $4$ 作为识别码。
+
+你的任务是编写程序判断输入的 ISBN 号码中识别码是否正确，如果正确，则仅输出 `Right`；如果错误，则输出你认为是正确的 ISBN 号码。
+
+## 输入格式
+
+一个字符序列，表示一本书的 ISBN 号码（保证输入符合 ISBN 号码的格式要求）。
+
+## 输出格式
+
+一行，假如输入的 ISBN 号码的识别码正确，那么输出 `Right`，否则，按照规定的格式，输出正确的 ISBN 号码（包括分隔符 `-`）。
+
+## 输入输出样例 #1
+
+### 输入 #1
+
+```
+0-670-82162-4
+```
+
+### 输出 #1
+
+```
+Right
+```
+
+## 输入输出样例 #2
+
+### 输入 #2
+
+```
+0-670-82162-0
+```
+
+### 输出 #2
+
+```
+0-670-82162-4
+```
+
diff --git a/week1-exercise3.out b/week1-exercise3.out
new file mode 100644
index 0000000..c555af9
--- /dev/null
+++ b/week1-exercise3.out
@@ -0,0 +1,10 @@
+Right
+0-670-82552-2
+9-670-82552-0
+0-445-82599-5
+0-445-81120-X
+Right
+Right
+9-670-87757-1
+9-222-87757-8
+9-222-11101-X