Problem:
Score : 100 points

Problem Statement

CODE FESTIVAL 2016 is going to be held. For the occasion, Mr. Takahashi decided to make a signboard.

He intended to write CODEFESTIVAL2016 on it, but he mistakenly wrote a different string S. Fortunately, the string he wrote was the correct length.

So Mr. Takahashi decided to perform an operation that replaces a certain character with another in the minimum number of iterations, changing the string to CODEFESTIVAL2016.

Find the minimum number of iterations for the rewrite operation.

Constraints

S is 16 characters long.

S consists of uppercase and lowercase alphabet letters and numerals.

Input

Inputs are provided from Standard Input in the following form.

S

Output

Output an integer representing the minimum number of iterations needed for the rewrite operation.

Sample Input 1

C0DEFESTIVAL2O16

Sample Output 1

2

The second character 0 must be changed to O and the 14th character O changed to 0.

Sample Input 2

FESTIVAL2016CODE

Sample Output 2

16

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

// Template from https://techracho.bpsinc.jp/jhonda/2019_08_05/78537

// input macro for competive-programming from https://qiita.com/tanakh/items/0ba42c7ca36cd29d0ac8
#[allow(unused_macros)]
macro_rules! input {
    (source = $s:expr, $($r:tt)*) => {
        input_inner!{$s, $($r)*}
    };
}

#[allow(unused_macros)]
macro_rules! input_inner {
    ($iter:expr) => {};
    ($iter:expr, ) => {};

    ($iter:expr, $var:ident : $t:tt $($r:tt)*) => {
        let $var = read_value!($iter, $t);
        input_inner!{$iter $($r)*}
    };

    ($iter:expr, mut $var:ident : $t:tt $($r:tt)*) => {
        let mut $var = read_value!($iter, $t);
        input_inner!{$iter $($r)*}
    };
}

#[allow(unused_macros)]
macro_rules! read_value {
    ($iter:expr, ( $($t:tt),* )) => {
        ( $(read_value!($iter, $t)),* )
    };

    ($iter:expr, [ $t:tt ; $len:expr ]) => {
        (0..$len).map(|_| read_value!($iter, $t)).collect::<Vec<_>>()
    };

    ($iter:expr, chars) => {
        read_value!($iter, String).chars().collect::<Vec<char>>()
    };

    ($iter:expr, bytes) => {
        read_value!($iter, String).into_bytes()
    };

    ($iter:expr, $t:ty) => {
        $iter.next().unwrap().parse::<$t>().expect("Parse error")
    };
}

fn main() {
    use std::io::Read;
    let mut s = String::new();
    std::io::stdin().read_to_string(&mut s).unwrap();

    println!("{}", solve(&s));
}

macro_rules! test {
    ($($exp_input:expr => $output:expr),* $(,)*) => {
        #[test]
        fn solve_test() {
            $(
                let start = std::time::Instant::now();
                let input = solve($exp_input);
                let end = start.elapsed();
                assert_eq!(input, $output, "{}.{:03}", end.as_secs(), end.subsec_millis());
                assert!(end.as_secs() <= 2, "expected_sec: {}sec, actual_sec: {}sec", 2, end.as_secs());
                assert!(end.as_secs() <= 1, "expected_sec: {}sec, actual_sec: {}sec", 1, end.as_secs());
                assert!(end.subsec_millis() <= 10, "expected_ms: {}ms, actual_ms: {}ms", 10, end.subsec_millis());
                assert!(end.subsec_millis() <= 2, "expected_ms: {}ms, actual_ms: {}ms", 2, end.subsec_millis());
            )*
        }
    };
}

test! {
r#"C0DEFESTIVAL2O16"# => r#"2"#,
}

fn solve(src: &str) -> String {
    let mut src_iter = src.split_whitespace();
    input! {
        source = src_iter,
        s: chars,
    }
    let cf = "CODEFESTIVAL2016".chars().collect::<Vec<char>>();
    let mut ans = 0;

    for i in 0..s.len() {
        if s[i] != cf[i] {
            ans += 1;
        }
    }

    ans.to_string()
}