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use std::env;
use std::io::BufReader;
use std::io::BufRead;
use std::fs::File;
use std::process;
#[macro_use] extern crate text_io;
struct BoundingBox {
left: u32,
top: u32,
right: u32,
bottom: u32
}
struct Coordinate {
x: u32,
y: u32
}
struct Point {
coordinate: Coordinate,
id: u32
}
fn distance(a: &Coordinate, b: &Coordinate) -> u32 {
let dx = (a.x as i32 - b.x as i32).abs();
let dy = (a.y as i32 - b.y as i32).abs();
(dx + dy) as u32
}
fn find_closest(c: &Coordinate, points: &Vec<Point>) -> Option<(u32, u32)> {
let mut shortest = std::u32::MAX;
let mut point_id: Option<u32> = None;
for point in points {
let dist = distance(&point.coordinate, c);
if dist < shortest {
shortest = dist;
point_id = Some(point.id);
} else if dist == shortest {
point_id = None;
}
}
match point_id {
Some(id) => Some((id, shortest)),
None => None
}
}
fn find_total_distance_to_points(c: &Coordinate, points: &Vec<Point>) -> u32 {
let mut total: u32 = 0;
for point in points {
let dist = distance(c, &point.coordinate);
total += dist;
}
total
}
fn draw_grid(grid: &Vec<Vec<Option<u32>>>, bb: &BoundingBox) {
let w = (bb.right - bb.left + 1) as usize;
let h = (bb.bottom - bb.top + 1) as usize;
for j in 0..h {
for i in 0..w {
let x = (i as u32 + bb.left) as u32;
let y = (j as u32 + bb.top) as u32;
let id_opt = grid[j][i];
match id_opt {
Some(id) => { print!("{}", id); }
None => { print!("."); }
}
}
print!("\n");
}
}
fn find_largest_area(grid: &Vec<Vec<Option<u32>>>, points: &Vec<Point>, bb: &BoundingBox) -> u32 {
let w = (bb.right - bb.left + 1) as usize;
let h = (bb.bottom - bb.top + 1) as usize;
let mut largest_area = 0;
for point in points {
let mut area = 0;
for j in 0..h {
for i in 0..w {
let id_opt = grid[j][i];
match id_opt {
Some(id) => {
if id == point.id {
area += 1;
}
}
None => {}
}
}
}
if area > largest_area {
largest_area = area;
}
}
largest_area
}
fn main() {
let args: Vec<String> = env::args().collect();
if args.len() != 2 {
println!("Wrong number of arguments. Provide just a file name.");
process::exit(1);
}
let filename = &args[1];
println!("Using file {} as input.", filename);
let f = match File::open(filename) {
Ok(file) => file,
Err(e) => {
println!("Failed to open file {}. {:?}", filename, e);
process::exit(1);
}
};
let file = BufReader::new(&f);
let lines: Vec<String> = file.lines()
.map(|line| line.expect("Could not parse line."))
.collect();
let mut points: Vec<Point> = Vec::new();
let mut bb: BoundingBox = BoundingBox {
left: std::u32::MAX,
top: std::u32::MAX,
right: std::u32::MIN,
bottom: std::u32::MIN
};
for (i, line) in (&lines).iter().enumerate() {
let (x, y): (u32, u32);
scan!(line.bytes() => "{}, {}", x, y);
if x < bb.left { bb.left = x; }
if x > bb.right { bb.right = x; }
if y < bb.top { bb.top = y; }
if y > bb.bottom { bb.bottom = y; }
let coordinate = Coordinate { x, y };
points.push(Point { coordinate, id: i as u32 });
println!("Add point {}, {}", &x, &y);
}
println!("BB: l: {}, r: {}, top: {}, bot: {}", bb.left, bb.right, bb.top, bb.bottom);
let w = (bb.right - bb.left + 1) as usize;
let h = (bb.bottom - bb.top + 1) as usize;
let mut grid: Vec<Vec<Option<u32>>> = vec![vec![None; w]; h];
for j in 0..h {
for i in 0..w {
let x = (i as u32 + bb.left) as u32;
let y = (j as u32 + bb.top) as u32;
let coord = Coordinate { x, y };
let opt: Option<(u32, u32)> = find_closest(&coord, &points);
match opt {
Some((id, shortest)) => { grid[j][i] = Some(id); }
None => { grid[j][i] = None }
}
}
}
//draw_grid(&grid, &bb);
let largest_area_1 = find_largest_area(&grid, &points, &bb);
println!("1. Largest area: {}", largest_area_1);
let threshold = 10000;
let mut largest_area_2 = 0;
for j in 0..h {
for i in 0..w {
let x = (i as u32 + bb.left) as u32;
let y = (j as u32 + bb.top) as u32;
let coord = Coordinate { x, y };
let total_dist = find_total_distance_to_points(&coord, &points);
if total_dist < threshold {
largest_area_2 += 1;
}
}
}
println!("2. Largest area: {}", largest_area_2);
}
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