Problem:
Score : 100 points

Problem Statement

Given is a string S representing the day of the week today.

S is SUN, MON, TUE, WED, THU, FRI, or SAT, for Sunday, Monday, Tuesday, Wednesday, Thursday, Friday, and Saturday, respectively.

After how many days is the next Sunday (tomorrow or later)?

Constraints

S is SUN, MON, TUE, WED, THU, FRI, or SAT.

Input

Input is given from Standard Input in the following format:

S

Output

Print the number of days before the next Sunday.

Sample Input 1

SAT

Sample Output 1

1

It is Saturday today, and tomorrow will be Sunday.

Sample Input 2

SUN

Sample Output 2

7

It is Sunday today, and seven days later, it will be Sunday again.

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

use std::io::BufRead;
use std::io::BufReader;

fn main() {
    let mut buf = BufReader::new(std::io::stdin());

    let mut s = String::new();
    buf.read_line(&mut s).unwrap();

    let s = s.trim();
    let ans = if s == "SUN" {
        7
    } else if s == "MON" {
        6
    } else if s == "TUE" {
        5
    } else if s == "WED" {
        4
    } else if s == "THU" {
        3
    } else if s == "FRI" {
        2
    } else {
        1
    };

    println!("{}", ans);
}