week2 essential mission added

.gitignore

@@ -0,0 +1,40 @@
+# Created by https://www.toptal.com/developers/gitignore/api/rust,visualstudiocode
+# Edit at https://www.toptal.com/developers/gitignore?templates=rust,visualstudiocode
+
+### Rust ###
+# Generated by Cargo
+# will have compiled files and executables
+debug/
+target/
+
+# Remove Cargo.lock from gitignore if creating an executable, leave it for libraries
+# More information here https://doc.rust-lang.org/cargo/guide/cargo-toml-vs-cargo-lock.html
+Cargo.toml
+Cargo.lock
+
+# These are backup files generated by rustfmt
+**/*.rs.bk
+
+# MSVC Windows builds of rustc generate these, which store debugging information
+*.pdb
+
+### VisualStudioCode ###
+.vscode/*
+!.vscode/settings.json
+!.vscode/tasks.json
+!.vscode/launch.json
+!.vscode/extensions.json
+!.vscode/*.code-snippets
+
+# Local History for Visual Studio Code
+.history/
+
+# Built Visual Studio Code Extensions
+*.vsix
+
+### VisualStudioCode Patch ###
+# Ignore all local history of files
+.history
+.ionide
+
+# End of https://www.toptal.com/developers/gitignore/api/rust,visualstudiocode

missions/week2/src/main.rs

@@ -0,0 +1,22 @@
+fn sum_array(input: &[i32]) -> i32 {
+    todo!();
+}
+
+fn swap(lhs: &mut String, rhs: &mut String) {
+    todo!();
+}
+
+fn main() {
+    let input_arr = [1, 2, 3, 4, 5];
+    let sum_arr = sum_array(&input_arr);
+    const SUM_RESULT: i32 = 15;
+    assert!(sum_arr == SUM_RESULT);
+    println!("{sum_arr} == {SUM_RESULT}");
+
+    let mut lhs = String::from("AAA");
+    let mut rhs = String::from("BBB");
+    swap(&mut lhs, &mut rhs);
+    assert!(lhs == "BBB");
+    assert!(rhs == "AAA");
+    println!("{lhs} {rhs}");
+}

ppt/2_ownership.md

@@ -376,4 +376,9 @@ let slice = &a[1..3];  // [2, 3]
 
 # 2주차 미션
 
----
+---
+
+![height:500px](../images/2_OwnerShip/03_essential_mission.png)
+
+- [저장소의 missions/week2/main.rs 완성하기](https://github.com/4roring/cheese-cRust/tree/master/missions/week2/main.rs)
+**(필수 미션)**