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use std::io;
use std::io::BufRead;
use std::str::FromStr;
struct Point {
x: usize,
y: usize
}
struct Claim {
id: i16,
origin: Point,
size: Point
}
impl FromStr for Claim {
type Err = std::num::ParseIntError;
fn from_str(s: &str) -> Result<Self, Self::Err> {
let bytes = s.as_bytes();
let mut cursor = 1;
let mut idx = 1;
while bytes[idx].is_ascii_digit() { idx += 1; }
let id = s[cursor..idx].parse()?;
idx = idx + 3;
cursor = idx;
while bytes[idx].is_ascii_digit() { idx += 1; }
let ox = s[cursor..idx].parse()?;
idx = idx + 1;
cursor = idx;
while bytes[idx].is_ascii_digit() { idx += 1; }
let oy = s[cursor..idx].parse()?;
idx = idx + 2;
cursor = idx;
while bytes[idx].is_ascii_digit() { idx += 1; }
let sx = s[cursor..idx].parse()?;
let sy = s[idx+1..].parse()?;
Ok(Claim {
id: id,
origin: Point {x: ox, y: oy},
size: Point {x: sx, y: sy}
})
}
}
pub fn main<T: BufRead>(reader: T) -> io::Result<(String, String)> {
let w = 1000;
let maxnum = 1500;
let mut sheet: Vec<i16> = vec![0; w * w];
let mut double: i64 = 0;
let mut free: Vec<bool> = vec![false; maxnum as usize];
for line in reader.lines() {
let claim = line.unwrap().parse::<Claim>().unwrap();
assert!(0 < claim.id && claim.id < maxnum);
free[claim.id as usize] = true;
for y in claim.origin.y .. claim.origin.y + claim.size.y {
for x in claim.origin.x .. claim.origin.x + claim.size.x {
let val = sheet[w * y + x];
if val > 0 {
free[val as usize] = false;
free[claim.id as usize] = false;
double += 1;
sheet[w * y + x] = -1;
} else if val == 0 {
sheet[w * y + x] = claim.id;
} else {
free[claim.id as usize] = false;
}
}
}
}
let part1 = double;
for i in 1 .. maxnum as usize {
if free[i] {
return Ok((part1.to_string(), i.to_string()));
}
}
Err(io::Error::new(io::ErrorKind::Other, "Invalid input"))
}
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