Problem:
Score : 200 points

Problem Statement

Let w be a string consisting of lowercase letters.
We will call w beautiful if the following condition is satisfied:

Each lowercase letter of the English alphabet occurs even number of times in w.

You are given the string w. Determine if w is beautiful.

Constraints

1 \leq |w| \leq 100

w consists of lowercase letters (a-z).

Input

The input is given from Standard Input in the following format:

w

Output

Print Yes if w is beautiful. Print No otherwise.

Sample Input 1

abaccaba

Sample Output 1

Yes

a occurs four times, b occurs twice, c occurs twice and the other letters occur zero times.

Sample Input 2

hthth

Sample Output 2

No

Solution in Rust (1.15.1) (judge verdict: Accepted)

use std::io::{Read, stdin};
use std::str::FromStr;
use std::collections::HashMap;

fn main(){
    let w :String = read();
    let mut m: HashMap<char, u32, _> = HashMap::new();
    let mut cnt: u32;
    for i in w.as_str().chars() {
        match m.get(&i) {
            Some(&j) => cnt = j + 1,
            None => cnt = 1,
        };
        m.insert(i, cnt);
    }
    let mut is_single: bool = true;
    for (_k, v) in &m {
        if v % 2 == 1 {is_single = false}
    }
    println!("{}", if is_single{ "Yes".to_string()}else{"No".to_string()});
}

fn read<T: FromStr>() -> T {
    let stdin = stdin();
    let stdin = stdin.lock();
    let token: String = stdin
        .bytes()
        .map(|c| c.expect("failed to read char") as char)
        .skip_while(|c| c.is_whitespace())
        .take_while(|c| !c.is_whitespace())
        .collect();
    token.parse().ok().expect("failed to parse token")
}