Problem:
Score : 100 points

Problem Statement

How many hours do we have until New Year at M o'clock (24-hour notation) on 30th, December?

Constraints

1≤M≤23

M is an integer.

Input

Input is given from Standard Input in the following format:

M

Output

If we have x hours until New Year at M o'clock on 30th, December, print x.

Sample Input 1

21

Sample Output 1

27

We have 27 hours until New Year at 21 o'clock on 30th, December.

Sample Input 2

12

Sample Output 2

36

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

use std::io::*;
use std::str::FromStr;

fn main(){
    println!("{}", 48-read_one::<i32>())
}

fn read_one<T: FromStr>() -> T {
    let stdin = stdin();
    let stdin = stdin.lock();
    let token: String = stdin.bytes().map(|c| c.expect("Error") as char) 
        .skip_while(|c| c.is_whitespace()).take_while(|c| !c.is_whitespace())
        .collect();
    token.parse().ok().expect("Error")
}
fn read_line<T: FromStr>() -> T{
    let mut buf = String::new();
    stdin().read_line(&mut buf).unwrap();
    buf.parse().ok().expect("Error")
}
fn read_vec<T: FromStr>() -> Vec<T>{
    let mut buf = String::new();
    stdin().read_line(&mut buf);
    let vec : Vec<&str> = buf.split_whitespace().collect();
    let mut v : Vec<T> = vec!();
    for i in 0..vec.len(){
        v.push(vec[i].parse().ok().expect("Error"));
    }
    v
}