Problem:
Score: 100 points

Problem Statement

The weather in Takahashi's town changes day by day, in the following cycle: Sunny, Cloudy, Rainy, Sunny, Cloudy, Rainy, ...

Given is a string S representing the weather in the town today. Predict the weather tomorrow.

Constraints

S is Sunny, Cloudy, or Rainy.

Input

Input is given from Standard Input in the following format:

S

Output

Print a string representing the expected weather tomorrow, in the same format in which input is given.

Sample Input 1

Sunny

Sample Output 1

Cloudy

In Takahashi's town, a sunny day is followed by a cloudy day.

Sample Input 2

Rainy

Sample Output 2

Sunny

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

use std::io::{self, BufRead, Write};

fn solve<R, W>(reader: R, mut writer: W)
where
    R: BufRead,
    W: Write,
{
    let mut lines = reader.lines();
    let a_line = lines.next().unwrap().unwrap();
    let ans = if a_line == "Sunny" {
        "Cloudy"
    } else if a_line == "Cloudy" {
        "Rainy"
    } else {
        "Sunny"
    };

    writeln!(&mut writer, "{}", ans).unwrap();
}

fn main() {
    let stdio = io::stdin();
    let input = stdio.lock();

    let output = io::stdout();

    solve(input, output);
}

#[cfg(test)]
mod tests {
    use super::*;

    const TESTS: &'static [(&'static [u8], &'static [u8])] = &[
        (
            br"Sunny", br"Cloudy
",
        ),
        (
            br"Rainy", br"Sunny
",
        ),
    ];

    #[test]
    fn test_a() {
        for &(input, expected) in TESTS {
            let mut output = Vec::new();
            solve(input, &mut output);
            let expected_str = String::from_utf8(expected.to_vec()).unwrap();
            let output_str = String::from_utf8(output).unwrap();
            assert_eq!(expected_str, output_str);
        }
    }
}