```

feat(day1): 新增猜数字游戏项目

- 添加 Rust 项目基础结构 (Cargo.toml, Cargo.lock)
- 实现猜数字游戏核心逻辑
- 集成随机数生成依赖 (rand 0.10.1)
- 添加 .gitignore 配置排除 target 目录
- 实现基本游戏循环和用户交互功能
```

.gitignore

@@ -0,0 +1 @@
+target/

day1/Cargo.lock

@@ -0,0 +1,77 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 4
+
+[[package]]
+name = "cfg-if"
+version = "1.0.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9330f8b2ff13f34540b44e946ef35111825727b38d33286ef986142615121801"
+
+[[package]]
+name = "chacha20"
+version = "0.10.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d524456ba66e72eb8b115ff89e01e497f8e6d11d78b70b1aa13c0fbd97540a81"
+dependencies = [
+ "cfg-if",
+ "cpufeatures",
+ "rand_core",
+]
+
+[[package]]
+name = "cpufeatures"
+version = "0.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8b2a41393f66f16b0823bb79094d54ac5fbd34ab292ddafb9a0456ac9f87d201"
+dependencies = [
+ "libc",
+]
+
+[[package]]
+name = "day1"
+version = "0.1.0"
+dependencies = [
+ "rand",
+]
+
+[[package]]
+name = "getrandom"
+version = "0.4.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "300e883d756b2e4ec94e02791f39b04b522276138852cfc41d9fb7e904106099"
+dependencies = [
+ "cfg-if",
+ "libc",
+ "r-efi",
+ "rand_core",
+]
+
+[[package]]
+name = "libc"
+version = "0.2.186"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "68ab91017fe16c622486840e4c83c9a37afeff978bd239b5293d61ece587de66"
+
+[[package]]
+name = "r-efi"
+version = "6.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f8dcc9c7d52a811697d2151c701e0d08956f92b0e24136cf4cf27b57a6a0d9bf"
+
+[[package]]
+name = "rand"
+version = "0.10.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d2e8e8bcc7961af1fdac401278c6a831614941f6164ee3bf4ce61b7edb162207"
+dependencies = [
+ "chacha20",
+ "getrandom",
+ "rand_core",
+]
+
+[[package]]
+name = "rand_core"
+version = "0.10.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "63b8176103e19a2643978565ca18b50549f6101881c443590420e4dc998a3c69"

day1/Cargo.toml

@@ -0,0 +1,7 @@
+[package]
+name = "day1"
+version = "0.1.0"
+edition = "2024"
+
+[dependencies]
+rand = "0.10.1"

day1/src/main.rs

@@ -0,0 +1,70 @@
+use std::{cmp::Ordering, io};
+
+fn main() {
+    println!("猜数游戏");
+    let secret_number: u32 = rand::random_range(1..=100);
+    // println!("The secret number is: {}", secret_number);
+    
+    let mut count = 0;
+    loop {
+        let mut guess = String::new();
+
+        println!("请输入你的猜测:");
+        io::stdin().read_line(&mut guess).expect("读取输入错误!");
+        let guess_number: u32 = match guess.trim().parse() {
+            Ok(num) => num,
+            Err(_) => {
+                println!("请输入数字!");
+                continue;
+            }
+        };
+
+        count += 1;
+
+        match guess_number.cmp(&secret_number) {
+            Ordering::Less => println!("小了!"),
+            Ordering::Greater => println!("大了!"),
+            Ordering::Equal => {
+                println!("猜对了!");
+                println!("你一共猜了{}次", count);
+                break;
+            }
+        }
+    }
+}
+
+/// 猜数字游戏 — 可指定数字范围，返回猜测次数
+fn guess_game(low: u32, high: u32) -> u32 {
+    let secret = rand::random_range(low..=high);
+    let mut guess = String::new();
+    let mut count = 0;
+
+    loop {
+        guess.clear();
+        println!("请输入你的猜测 ({low}~{high}):");
+        io::stdin().read_line(&mut guess).expect("读取输入错误!");
+
+        let guess_num: u32 = match guess.trim().parse() {
+            Ok(n) if n < low || n > high => {
+                println!("数字不在范围内，请重新输入!");
+                continue;
+            }
+            Ok(n) => n,
+            Err(_) => {
+                println!("请输入有效的数字!");
+                continue;
+            }
+        };
+
+        count += 1;
+
+        match guess_num.cmp(&secret) {
+            Ordering::Less => println!("小了!"),
+            Ordering::Greater => println!("大了!"),
+            Ordering::Equal => {
+                println!("猜对了! 答案是 {secret}，你一共猜了 {count} 次");
+                return count;
+            }
+        }
+    }
+}