Add dev container

Author: calebkiage

.devcontainer/Dockerfile

@@ -0,0 +1,9 @@
+# See here for image contents: https://github.com/microsoft/vscode-dev-containers/tree/v0.245.0/containers/rust/.devcontainer/base.Dockerfile
+
+# [Choice] Debian OS version (use bullseye on local arm64/Apple Silicon): buster, bullseye
+ARG VARIANT="buster"
+FROM mcr.microsoft.com/vscode/devcontainers/rust:0-${VARIANT}
+
+# [Optional] Uncomment this section to install additional packages.
+# RUN apt-get update && export DEBIAN_FRONTEND=noninteractive \
+#     && apt-get -y install --no-install-recommends <your-package-list-here>

.devcontainer/devcontainer.json

@@ -0,0 +1,55 @@
+// For format details, see https://aka.ms/devcontainer.json. For config options, see the README at:
+// https://github.com/microsoft/vscode-dev-containers/tree/v0.245.0/containers/rust
+{
+	"name": "Rust",
+	"build": {
+		"dockerfile": "Dockerfile",
+		"args": {
+			// Use the VARIANT arg to pick a Debian OS version: buster, bullseye
+			// Use bullseye when on local on arm64/Apple Silicon.
+			"VARIANT": "bullseye"
+		}
+	},
+	"runArgs": [
+		"--cap-add=SYS_PTRACE",
+		"--security-opt",
+		"seccomp=unconfined"
+	],
+
+	// Configure tool-specific properties.
+	"customizations": {
+		// Configure properties specific to VS Code.
+		"vscode": {
+			// Set *default* container specific settings.json values on container create.
+			"settings": { 
+				"lldb.executable": "/usr/bin/lldb",
+				// VS Code don't watch files under ./target
+				"files.watcherExclude": {
+					"**/target/**": true
+				},
+				"rust-analyzer.checkOnSave.command": "clippy"
+			},
+			
+			// Add the IDs of extensions you want installed when the container is created.
+			"extensions": [
+				"vadimcn.vscode-lldb",
+				"mutantdino.resourcemonitor",
+				"rust-lang.rust-analyzer",
+				"tamasfe.even-better-toml",
+				"serayuzgur.crates"
+			]
+		}
+	},
+
+	// Use 'forwardPorts' to make a list of ports inside the container available locally.
+	// "forwardPorts": [],
+
+	// Use 'postCreateCommand' to run commands after the container is created.
+	// "postCreateCommand": "rustc --version",
+
+	// Comment out to connect as root instead. More info: https://aka.ms/vscode-remote/containers/non-root.
+	"remoteUser": "vscode",
+	"features": {
+		"git": "os-provided"
+	}
+}

array-rotate/src/lib.rs

@@ -1,12 +1,12 @@
 fn rotate(array: &[i32], factor: i32) -> Vec<i32> {
-    let append = if factor > 0 { false } else { true };
+    let append = factor <= 0;
     let length: usize = array.len();
     if length < 1 {
         return Vec::with_capacity(0);
     }
     // Remove sign
     let mut f: usize = if factor < 0 { !factor + 1 } else { factor } as usize;
-    f = f % length;
+    f %= length;
     let mut response: Vec<i32> = Vec::with_capacity(length);
 
     for i in 0..length {
@@ -16,16 +16,14 @@ fn rotate(array: &[i32], factor: i32) -> Vec<i32> {
             } else {
                 response.push(array[i - f]);
             }
+        } else if i < length - f {
+            response.push(array[i + f]);
         } else {
-            if i < length - f {
-                response.push(array[i + f]);
-            } else {
-                response.push(array[i + f - length]);
-            }
+            response.push(array[i + f - length]);
         }
     }
 
-    return response;
+    response
 }
 
 #[cfg(test)]

sorting/src/merge_sort/mod.rs

@@ -33,11 +33,8 @@ pub fn top_down_merge_sort_par(input: &mut [i32], work: &mut [i32]) {
     let result = rayon::ThreadPoolBuilder::new()
         .num_threads(num_cpus::get() - 2)
         .build();
-    match result {
-        Ok(pool) => {
-            top_down_split_merge_par(input, work, &pool);
-        }
-        Err(_) => {}
+    if let Ok(pool) = result {
+        top_down_split_merge_par(input, work, &pool);
     }
 }
 
@@ -98,7 +95,7 @@ pub fn bottom_up_merge_sort(input: &mut [i32], work: &mut [i32]) {
             );
 
             // Same as i + 2 * width
-            i = i + width_x2;
+            i += width_x2;
         }
 
         // Now work array is full of runs of length 2*width.