/*
 * @lc app=leetcode id=349 lang=rust
 *
 * [349] Intersection of Two Arrays
 *
 * https://leetcode.com/problems/intersection-of-two-arrays/description/
 *
 * algorithms
 * Easy (59.84%)
 * Total Accepted:    314.7K
 * Total Submissions: 525.3K
 * Testcase Example:  '[1,2,2,1]\n[2,2]'
 *
 * Given two arrays, write a function to compute their intersection.
 * 
 * Example 1:
 * 
 * 
 * Input: nums1 = [1,2,2,1], nums2 = [2,2]
 * Output: [2]
 * 
 * 
 * 
 * Example 2:
 * 
 * 
 * Input: nums1 = [4,9,5], nums2 = [9,4,9,8,4]
 * Output: [9,4]
 * 
 * 
 * Note:
 * 
 * 
 * Each element in the result must be unique.
 * The result can be in any order.
 * 
 * 
 * 
 * 
 */
impl Solution {
    pub fn intersection(a: Vec<i32>, b: Vec<i32>) -> Vec<i32> {
        let sa:HashSet<i32> = a.into_iter().collect();
        let sb:HashSet<i32> = b.into_iter().collect();
        sa.intersection(&sb).map(|n| *n).collect()
    }
}


// pub structSolution; 

use std::collections::HashMap;
use std::collections::HashSet;
use std::fmt::Debug;
use std::hash::Hash;
use std::iter::FromIterator;
// use std::collections::VecDeque; 
// use std::collections::BTreeMap; 

#[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 
}

#[allow(dead_code)]
pub fn vec_counter(arr: Vec<i32>) -> HashMap<i32, i32> {
    let mut c = HashMap::new(); 
    for n in arr { *c.entry(n).or_insert(0) += 1; }
    c 
}

#[allow(dead_code)]
pub fn vec_to_hashset(arr: Vec<i32>) -> HashSet<i32> {
   HashSet::from_iter(arr.iter().cloned())
}

#[allow(dead_code)]
pub fn int_to_char(n: i32) -> char {
    // Convert number 0 to a, 1 to b, ...
    assert!(n >= 0 && n <= 25);
    (n as u8 + 'a' as u8) as char
}

#[allow(dead_code)]
fn sayi32(i: i32) {
	println!("{}", i);
}

#[allow(dead_code)]
fn sayi32_arr(arr: &Vec<i32>) {
	println!("{:?}", arr);
}

#[allow(dead_code)]
pub fn bisect_left(arr: &Vec<i32>, target: i32) -> usize {
    let (mut lo, mut hi) = (0, arr.len() - 1);
    let mut mid;
    while lo < hi {
        mid = (lo + hi) >> 1; 
        if arr[mid as usize] >= target { hi = mid; }
        else { lo = mid + 1; }
    }
    lo 
 }

 #[allow(dead_code)]
pub fn bisect_right(arr: &Vec<i32>, target: i32) -> usize {
    let (mut lo, mut hi) = (0, arr.len() - 1);
    let mut mid;
    while lo < hi {
        mid = (lo + hi + 1) >> 1; 
        if arr[mid as usize] > target { hi = mid - 1; }
        else { lo = mid; }
    }
    if arr[hi] > target { hi } else {hi + 1}
}