/*
 * @lc app=leetcode id=1365 lang=rust
 *
 * [1365] How Many Numbers Are Smaller Than the Current Number
 *
 * https://leetcode.com/problems/how-many-numbers-are-smaller-than-the-current-number/description/
 *
 * algorithms
 * Easy (85.26%)
 * Total Accepted:    29.6K
 * Total Submissions: 34.7K
 * Testcase Example:  '[8,1,2,2,3]'
 *
 * Given the array nums, for each nums[i] find out how many numbers in the
 * array are smaller than it. That is, for each nums[i] you have to count the
 * number of valid j's such that j != i and nums[j] < nums[i].
 * 
 * Return the answer in an array.
 * 
 * 
 * Example 1:
 * 
 * 
 * Input: nums = [8,1,2,2,3]
 * Output: [4,0,1,1,3]
 * Explanation: 
 * For nums[0]=8 there exist four smaller numbers than it (1, 2, 2 and 3). 
 * For nums[1]=1 does not exist any smaller number than it.
 * For nums[2]=2 there exist one smaller number than it (1). 
 * For nums[3]=2 there exist one smaller number than it (1). 
 * For nums[4]=3 there exist three smaller numbers than it (1, 2 and 2).
 * 
 * 
 * Example 2:
 * 
 * 
 * Input: nums = [6,5,4,8]
 * Output: [2,1,0,3]
 * 
 * 
 * Example 3:
 * 
 * 
 * Input: nums = [7,7,7,7]
 * Output: [0,0,0,0]
 * 
 * 
 * 
 * Constraints:
 * 
 * 
 * 2 <= nums.length <= 500
 * 0 <= nums[i] <= 100
 * 
 */
impl Solution {
    pub fn smaller_numbers_than_current(nums: Vec<i32>) -> Vec<i32> {
        let mut cns:Vec<i32> = nums.to_vec();
        cns.sort();

        let mut hm: HashMap<i32, i32> = HashMap::new();
        for (i, n) in cns.iter().enumerate(){
            if !hm.contains_key(n) { hm.insert(*n, i as i32); }
        }
        // let res:Vec<i32> =
        nums.iter().map(|n| hm[n]).collect::<Vec<i32>>()
        // println!("{:?}", res);
        // nums
    }
}


// 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}
}