Submission #1662439

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Source Code Expand

use std::io::{stdin, Read, StdinLock};
use std::str::FromStr;


fn main(){
    let cin = stdin();
    let cin = cin.lock();
    let mut sc = Scanner::new(cin);

    // SSS => o
    // SSW => x
    // SWS => x
    // SWW => o
    // WWW => o
    
    while let Some(N) = sc.read1() {
        let s = sc.read::<String>();
        let s: Vec<i32> = s.chars()
            .map(|e| if e == 'o' { 1 } else { 0 })
            .collect();

        let mut found = false;
        for i in 0..4 {
            let mut cand = vec![0 as i32; N];
            cand[0] = i & 1;
            cand[1] = (i >> 1) & 1;

            //  j.......
            // 012345678(N-1)
            for j in 2..N {
                cand[j] = cand[j - 2] ^ cand[j - 1] ^ s[j - 1];
            }

            if s[0] == cand[N - 1] ^ cand[0] ^ cand[1] && s[N - 1] == cand[N - 2] ^ cand[N - 1] ^ cand[0] {
                for e in cand {
                    print!("{}", if e == 1 { "S" } else { "W" });
                }
                println!();
                found = true;
                break;
            }
        }

        if !found {
            println!("-1");
        }
    }
}

//=============================================================================

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()
    }
}

Submission Info

Compile Error

warning: variable `N` should have a snake case name such as `n`, #[warn(non_snake_case)] on by default
  --> ./Main.rs:16:20
   |
16 |     while let Some(N) = sc.read1() {
   |                    ^

Judge Result