键优先队列

Rust库，支持在队列中更改优先级项或提前删除。要更改优先级，您需要使用某些键。

Cargo.toml强制执行的最低支持的Rust版本。

用法

代码示例

use keyed_priority_queue::{KeyedPriorityQueue, Entry};

let mut queue = KeyedPriorityQueue::new();

// Currently queue is empty
assert_eq!(queue.peek(), None);

queue.push("Second", 4);
queue.push("Third", 3);
queue.push("First", 5);
queue.push("Fourth", 2);
queue.push("Fifth", 1);

// Peek return references to most important pair.
assert_eq!(queue.peek(), Some((&"First", &5)));

assert_eq!(queue.len(), 5);

// We can clone queue if both key and priority is clonable
let mut queue_clone = queue.clone();

// We can run consuming iterator on queue,
// and it will return items in decreasing order
for (key, priority) in queue_clone{
    println!("Priority of key {} is {}", key, priority);
}

// Popping always will return the biggest element
assert_eq!(queue.pop(), Some(("First", 5)));
// We can change priority of item by key:
queue.set_priority(&"Fourth", 10);
// And get it
assert_eq!(queue.get_priority(&"Fourth"), Some(&10));
// Now biggest element is Fourth
assert_eq!(queue.pop(), Some(("Fourth", 10)));
// We can also decrease priority!
queue.set_priority(&"Second", -1);
assert_eq!(queue.pop(), Some(("Third", 3)));
assert_eq!(queue.pop(), Some(("Fifth", 1)));
assert_eq!(queue.pop(), Some(("Second", -1)));
// Now queue is empty
assert_eq!(queue.pop(), None);

// There are Entry API if you want to avoid double hash lookups
match queue.entry("Entry"){
    Entry::Vacant(entry)=>entry.set_priority(10),
    Entry::Occupied(_)=>unreachable!(),
};

match queue.entry("Entry"){
    Entry::Vacant(_)=>unreachable!(),
    Entry::Occupied(entry)=>{
        assert_eq!(entry.get_key(), &"Entry");
        assert_eq!(entry.get_priority(), &10);
        entry.set_priority(5);
    },
};

// We can clear queue
queue.clear();
assert!(queue.is_empty());