Clippy and refactor (#18)

* now lint with clippy

* consistency

* asdf

* install verifyer helper tool later

* fix unused var

* revert

* add back in clippy

* fix clippy warnings

* [auto-verifier] verify commit f96bc61

* better way

* [auto-verifier] verify commit bc8f6ea

* revert

* less diff

* [auto-verifier] verify commit 22d5e9f

* new CI file

* set up rust

* [auto-verifier] verify commit 15ead42

* increase time limit

* only build as we use oj verify to test

* [auto-verifier] verify commit 13d63c5

* to test CI

* revert

* no longer keep timestamp file since all tests will run each time

* comment some reasons

---------

Co-authored-by: Luke Videckis <lukevideckis@gmail.com>
Co-authored-by: GitHub <noreply@github.com>

Author: lrvideckis

.github/workflows/ci.yml

@@ -2,34 +2,55 @@ name: CI
 
 on: [push, workflow_dispatch]
 
+env:
+  CARGO_TERM_COLOR: always
+  # causes CI to fail on any warning
+  RUSTFLAGS: -D warnings
+  RUSTDOCFLAGS: -D warnings
+
 jobs:
-  verify:
+  cargo:
     runs-on: ubuntu-latest
-    permissions:
-      contents: write
-
     steps:
     - uses: actions/checkout@v3
-
     - uses: actions/setup-python@v4
-
-    - name: install oj-verify
-      run: pip3 install -U online-judge-verify-helper
-
     - name: Set up Rust (nightly)
       run: |
         rustup install nightly
         rustup override set nightly
-        rustup component add --toolchain nightly rustfmt
-
+        rustup component add --toolchain nightly rustfmt clippy
     - name: cargo fmt
       run: cargo fmt --all -- --check
+    - name: cargo clippy
+      run: cargo clippy --all-targets --all-features -- -D warnings
+    - name: cargo build
+      run: cargo build --verbose
 
-    - name: cargo test
-      # RUSTFLAGS="-D warnings" will fail CI on any compile warning
-      run: RUSTFLAGS="-D warnings" cargo test
-
+  library_checker_aizu_tests:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v3
+    - uses: actions/setup-python@v4
+    - name: install oj-verify
+      run: pip3 install -U online-judge-verify-helper
+    - name: Set up Rust (nightly)
+      run: |
+        rustup install nightly
+        rustup override set nightly
+        rustup component add --toolchain nightly rustfmt clippy
     - name: use oj-verify
-      env:
-        GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
-      run: oj-verify all --tle 1
+      # regarging `--tle 2`: the oj-verify tool only allows testing in release mode
+      #
+      # regarding `--jobs 4`: github CI runs with 4 cores
+      # https://docs.github.com/en/actions/using-github-hosted-runners/about-github-hosted-runners/about-github-hosted-runners#standard-github-hosted-runners-for-public-repositories
+      #
+      # regarding `--timeout `: github CI limits jobs to 6 hours
+      # https://docs.github.com/en/actions/learn-github-actions/usage-limits-billing-and-administration#usage-limits
+      #
+      # since the library is a single crate, on a commit the entire crate is
+      # rebuild, so oj-verify tool thinks everything changed, and then reruns all
+      # tests; thus another reason for setting long timeout.
+      #
+      # since all tests are rerun on every commit anyways, there's no need for
+      # the .verify-helper/timestamps.remote.json file
+      run: oj-verify all --tle 2 --jobs 4 --timeout 21600

.gitignore

@@ -1,2 +1,3 @@
 /target
 Cargo.lock
+.verify-helper/

.verify-helper/timestamps.remote.json

@@ -12,8 +12,8 @@ fn main() {
     }
 
     let mut fenwick = Fenwick::<u64>::new(n);
-    for i in 0..n {
-        fenwick.add(i, a[i] as u64);
+    for (i, &elem) in a.iter().enumerate() {
+        fenwick.add(i, elem as u64);
     }
 
     for que in queries {

examples/point_add_range_sum.rs

@@ -1,9 +1,9 @@
 use std::cmp::Reverse;
 use std::collections::BinaryHeap;
 
-pub fn dijk(adj: &Vec<Vec<(usize, u64)>>, s: usize) -> Vec<u64> {
+pub fn dijk(adj: &[Vec<(usize, u64)>], s: usize) -> Vec<u64> {
     let n = adj.len();
-    let mut dist = vec![std::u64::MAX; n];
+    let mut dist = vec![u64::MAX; n];
     let mut q = BinaryHeap::new();
     q.push(Reverse((0, s)));
     while let Some(Reverse((d, u))) = q.pop() {

src/dijk.rs

@@ -3,8 +3,8 @@ pub struct RMQ<T> {
     op: fn(T, T) -> T,
 }
 impl<T: Copy> RMQ<T> {
-    pub fn new(a: &Vec<T>, op: fn(T, T) -> T) -> Self {
-        let mut t = vec![a.clone(); 1];
+    pub fn new(a: &[T], op: fn(T, T) -> T) -> Self {
+        let mut t = vec![a.to_owned(); 1];
         let mut i = 0;
         while (2 << i) <= a.len() {
             t.push(