use std::iter::Iterator;
use std::io::{Result, Read};
pub trait SimpleIO {
fn read_string(&mut self) -> Result<String>;
fn read_chars(&mut self) -> Result<Vec<char>>;
fn read_lines(&mut self) -> Result<Vec<String>>;
fn read_vec(&mut self) -> Result<Vec<u8>>;
}
pub struct Chars {
index: usize,
inner: Vec<char>
}
impl Iterator for Chars {
type Item = char;
fn next(&mut self) -> Option<char> {
self.index += 1;
self.inner.get(self.index)
.map(|x| *x)
}
}
impl Chars {
pub fn first(&self) -> Option<char> {
self.inner.get(0)
.map(|x| *x)
}
pub fn get(&self, idx: usize) -> Option<char> {
self.inner.get(idx)
.map(|x| *x)
}
pub fn from(src: Vec<char>) -> Chars {
Chars {
index: 0,
inner: src,
}
}
}
pub struct Lines {
index: usize,
inner: Vec<String>,
}
impl Iterator for Lines {
type Item = String;
fn next(&mut self) -> Option<String> {
self.index += 1;
self.inner.get(self.index)
.map(|x| x.clone())
}
}
impl Lines {
pub fn first(&self) -> Option<String> {
self.inner.get(0)
.map(|x| x.clone())
}
pub fn get(&self, idx: usize) -> Option<String> {
self.inner.get(idx)
.map(|x| x.clone())
}
pub fn from(src: Vec<String>) -> Lines {
Lines {
index: 0,
inner: src,
}
}
}
impl<T> SimpleIO for T
where T: Read
{
fn read_string(&mut self) -> Result<String> {
let mut buf = String::new();
self.read_to_string(&mut buf)
.map(|_| buf)
}
fn read_chars(&mut self) -> Result<Vec<char>> {
let mut buf = String::new();
self.read_to_string(&mut buf)
.map(|_| buf.chars().collect())
}
fn read_lines(&mut self) -> Result<Vec<String>> {
let mut buf = String::new();
self.read_to_string(&mut buf)
.map(|_| buf.lines().map(|x| x.to_string()).collect())
}
fn read_vec(&mut self) -> Result<Vec<u8>> {
let mut buf = Vec::new();
self.read_to_end(&mut buf)
.map(|_| buf)
}
}