/*
 * @lc app=leetcode id=933 lang=rust
 *
 * [933] Number of Recent Calls
 *
 * https://leetcode.com/problems/number-of-recent-calls/description/
 *
 * algorithms
 * Easy (70.51%)
 * Total Accepted:    37.6K
 * Total Submissions: 53.3K
 * Testcase Example:  '["RecentCounter","ping","ping","ping","ping"]\n[[],[1],[100],[3001],[3002]]'
 *
 * Write a class RecentCounter to count recent requests.
 * 
 * It has only one method: ping(int t), where t represents some time in
 * milliseconds.
 * 
 * Return the number of pings that have been made from 3000 milliseconds ago
 * until now.
 * 
 * Any ping with time in [t - 3000, t] will count, including the current ping.
 * 
 * It is guaranteed that every call to ping uses a strictly larger value of t
 * than before.
 * 
 * 
 * 
 * Example 1:
 * 
 * 
 * Input: inputs = ["RecentCounter","ping","ping","ping","ping"], inputs =
 * [[],[1],[100],[3001],[3002]]
 * Output: [null,1,2,3,3]
 * 
 * 
 * 
 * Note:
 * 
 * 
 * Each test case will have at most 10000 calls to ping.
 * Each test case will call ping with strictly increasing values of t.
 * Each call to ping will have 1 <= t <= 10^9.
 * 
 * 
 * 
 * 
 * 
 */

use std::borrow::BorrowMut;
use std::collections::VecDeque;

struct RecentCounter {
    q: VecDeque<i32>,
}


/** 
 * `&self` means the method takes an immutable reference.
 * If you need a mutable reference, change it to `&mut self` instead.
 */
impl RecentCounter {

    fn new() -> Self {
        RecentCounter{
            q: VecDeque::new(),
        }
    }
    
    pub fn ping(&mut self, t: i32) -> i32 {
        let q = self.q.borrow_mut();
        q.push_back(t);
        while let Some(v) = q.front() {
            if *v < t - 3000 {
                q.pop_front();
            } else {
                break; 
            }
        }
        q.len() as i32
    }
}

/**
 * Your RecentCounter object will be instantiated and called as such:
 * let obj = RecentCounter::new();
 * let ret_1: i32 = obj.ping(t);
 */

use std::collections::HashMap;
use std::fmt::Debug;
use std::hash::Hash;

#[allow(dead_code)]
pub fn print_map<K: Debug + Eq + Hash, V: Debug>(map: &HashMap<K, V>) {
    for (k, v) in map.iter() {
        println!("{:?}: {:?}", k, v);
    }
}

#[allow(dead_code)]
pub fn say_vec(nums: Vec<i32>){
	println!("{:?}", nums);
}

#[allow(dead_code)]
pub fn char_frequency(s: String) -> HashMap<char, i32> {
    let mut res:HashMap<char, i32> = HashMap::new(); 
    for c in s.chars(){
        *res.entry(c).or_insert(0) += 1;
    }
    res 
}