Решение на упр.04 задача 2 от Борис Великов
Резултати
- 2 точки от тестове
- 0 бонус точки
- 2 точки общо
- 3 успешни тест(а)
- 1 неуспешни тест(а)
Код
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
enum CompareResult {
Less,
Equal,
Greater,
}
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
enum SortOrder {
Desc,
Asc,
}
trait Compare {
fn compare(&self, other: &Self) -> CompareResult;
}
trait Filter {
fn matches(&self, query: &str) -> bool;
}
trait Aggregate {
type Output;
fn aggregate(items: &[Self]) -> Self::Output
where
Self: Sized;
}
#[derive(Clone)]
struct Book {
title: String,
author: String,
year: u32,
rating: f32,
}
impl Compare for Book{
fn compare(&self, other: &Self) -> CompareResult{
let mut res:CompareResult;
if self.year == other.year{
res = CompareResult::Equal;
}
if self.year > other.year{
res = CompareResult::Greater;
}else{
res = CompareResult::Less;
}
res
}
}
impl Filter for Book{
fn matches(&self, query: &str) -> bool{
self.author.contains(query) || self.title.contains(query)
}
}
impl Aggregate for Book{
type Output = f32;
fn aggregate(items: &[Self]) -> Self::Output where Self: Sized {
if items.is_empty(){
return 0.0;
}
let mut sum: f32 = 0.0;
for b in items {
sum += b.rating;
}
sum/items.len() as f32
}
}
fn process_items<T>(items: Vec<T>, query: &str, order: SortOrder)
-> (Vec<T>, T::Output) where T: Compare + Filter + Aggregate + Clone,
{
//filter
let mut filtered: Vec<T> = items
.into_iter()
.filter(|item| item.matches(query))
.collect();
//bubble sort
for i in 0..filtered.len().saturating_sub(1){
for j in i..filtered.len().saturating_sub(1){
let comparisson: CompareResult = filtered[j].compare(&filtered[j+1]);
if order == SortOrder::Asc{
if comparisson == CompareResult::Greater{
filtered.swap(j,j+1);
}
}else{
if comparisson == CompareResult::Less{
filtered.swap(j,j+1);
}
}
}
}
//aggregate
let aggregated = T::aggregate(&filtered);
(filtered,aggregated)
}
fn main(){
let books = vec![
Book { title: "The Rust Book".into(), author: "Steve".into(), year: 2018, rating: 4.7 },
Book { title: "Rust Patterns".into(), author: "Anna".into(), year: 2020, rating: 4.9 },
Book { title: "C Programming".into(), author: "Dennis".into(), year: 1978, rating: 4.3 },
];
let (result, avg_rating) = process_items(books, "Rust", SortOrder::Asc);
println!("Filtered & sorted:");
for b in &result {
println!("{} by {} ({})", b.title, b.author, b.year);
}
println!("Average rating: {:.2}", avg_rating);
}
Лог от изпълнението
Updating crates.io index
Locking 17 packages to latest compatible versions
Compiling proc-macro2 v1.0.103
Compiling unicode-ident v1.0.22
Compiling quote v1.0.41
Compiling futures-core v0.3.31
Compiling futures-sink v0.3.31
Compiling futures-channel v0.3.31
Compiling memchr v2.7.6
Compiling syn v2.0.109
Compiling pin-utils v0.1.0
Compiling futures-task v0.3.31
Compiling pin-project-lite v0.2.16
Compiling futures-io v0.3.31
Compiling slab v0.4.11
Compiling solution v0.1.0 (/tmp/d20251106-1757769-125wjyf/solution)
warning: value assigned to `res` is never read
--> src/lib.rs:41:13
|
41 | res = CompareResult::Equal;
| ^^^
|
= help: maybe it is overwritten before being read?
= note: `#[warn(unused_assignments)]` on by default
warning: enum `CompareResult` is never used
--> src/lib.rs:2:6
|
2 | enum CompareResult {
| ^^^^^^^^^^^^^
|
= note: `#[warn(dead_code)]` on by default
warning: enum `SortOrder` is never used
--> src/lib.rs:9:6
|
9 | enum SortOrder {
| ^^^^^^^^^
warning: trait `Compare` is never used
--> src/lib.rs:14:7
|
14 | trait Compare {
| ^^^^^^^
warning: trait `Filter` is never used
--> src/lib.rs:18:7
|
18 | trait Filter {
| ^^^^^^
warning: trait `Aggregate` is never used
--> src/lib.rs:22:7
|
22 | trait Aggregate {
| ^^^^^^^^^
warning: struct `Book` is never constructed
--> src/lib.rs:30:8
|
30 | struct Book {
| ^^^^
warning: function `process_items` is never used
--> src/lib.rs:75:4
|
75 | fn process_items<T>(items: Vec<T>, query: &str, order: SortOrder)
| ^^^^^^^^^^^^^
warning: function `main` is never used
--> src/lib.rs:103:4
|
103 | fn main(){
| ^^^^
warning: `solution` (lib) generated 9 warnings
Compiling futures-macro v0.3.31
Compiling futures-util v0.3.31
Compiling futures-executor v0.3.31
Compiling futures v0.3.31
warning: value assigned to `res` is never read
--> tests/../src/lib.rs:41:13
|
41 | res = CompareResult::Equal;
| ^^^
|
= help: maybe it is overwritten before being read?
= note: `#[warn(unused_assignments)]` on by default
warning: function `main` is never used
--> tests/../src/lib.rs:103:4
|
103 | fn main(){
| ^^^^
|
= note: `#[warn(dead_code)]` on by default
warning: `solution` (test "solution_test") generated 2 warnings
Finished `test` profile [unoptimized + debuginfo] target(s) in 8.82s
Running tests/solution_test.rs (target/debug/deps/solution_test-8c2c5f784503f204)
running 4 tests
test solution_test::test_aggregate ... ok
test solution_test::test_compare ... FAILED
test solution_test::test_matches ... ok
test solution_test::test_process ... ok
failures:
---- solution_test::test_compare stdout ----
thread 'solution_test::test_compare' panicked at tests/solution_test.rs:53:5:
assertion `left == right` failed
left: Less
right: Equal
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
failures:
solution_test::test_compare
test result: FAILED. 3 passed; 1 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s
error: test failed, to rerun pass `--test solution_test`