Problem:
Score : 100 points

Problem Statement

You are given three words s_1, s_2 and s_3, each composed of lowercase English letters, with spaces in between.
Print the acronym formed from the uppercased initial letters of the words.

Constraints

s_1, s_2 and s_3 are composed of lowercase English letters.

1 ≤ |s_i| ≤ 10 (1≤i≤3)

Input

Input is given from Standard Input in the following format:

s_1 s_2 s_3

Output

Print the answer.

Sample Input 1

atcoder beginner contest

Sample Output 1

ABC

The initial letters of atcoder, beginner and contest are a, b and c. Uppercase and concatenate them to obtain ABC.

Sample Input 2

resident register number

Sample Output 2

RRN

Sample Input 3

k nearest neighbor

Sample Output 3

KNN

Sample Input 4

async layered coding

Sample Output 4

ALC

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

use std::io::{stdin, Read, StdinLock};
use std::str::FromStr;
use std::vec::Vec;
use std::{vec, cmp, num};


struct Scanner<'a> {
    cin: StdinLock<'a>,
}

impl<'a> Scanner<'a> {
    fn new(cin: StdinLock<'a>) -> Scanner<'a> {
        Scanner {cin: cin}
    }

    fn read1<T: FromStr>(&mut self) -> Option<T> {
        let token = self.cin.by_ref().bytes().map(|c| c.unwrap() as char)
                    .skip_while(|c| c.is_whitespace())
                    .take_while(|c| !c.is_whitespace())
                    .collect::<String>();
        token.parse::<T>().ok()
    }

    fn read<T: FromStr>(&mut self) -> T {
        self.read1().unwrap()
    }
}

// create Vec<char> from String
#[allow(dead_code)]
fn to_chars(s: String) -> vec::Vec<char> {
    let mut cs = s.chars();
    let mut res = vec::Vec::new();
    while let Some(c) = cs.next() {
        res.push(c);
    }
    res
}

fn main() {
    let cin = stdin();
    let cin = cin.lock();
    let mut sc = Scanner::new(cin);
    let mut s: Vec<Vec<char>> = Vec::new();
    for _i in 0..3 {
        let t: String = sc.read();
        s.push(to_chars(t));
    }
    println!("{}{}{}", s[0][0].to_uppercase().next().expect(""),
                       s[1][0].to_uppercase().next().expect(""),
                       s[2][0].to_uppercase().next().expect(""));
}