Solve day3

1 files changed, 87 insertions, 0 deletions

diff --git a/day3/src/main.rs b/day3/src/main.rs
new file mode 100644
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+++ b/day3/src/main.rs
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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 Claim {
+  _id: u32,
+  x: u32,
+  y: u32,
+  width: u32,
+  height: u32
+}
+
+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 mut claims: Vec<Claim> = Vec::new();
+  let mut max_width = 0;
+  let mut max_height = 0;
+  // exercise 1
+  for line in file.lines() {
+    let l = line.unwrap();
+    let (id, x, y, width, height): (u32, u32, u32, u32, u32);
+    scan!(l.bytes() => "#{} @ {},{}: {}x{}", id, x, y, width, height);
+    if x + width > max_width {
+      max_width = x + width;
+    }
+    if y + height > max_height {
+      max_height = y + height;
+    }
+    let claim = Claim { _id: id, x, y, width, height };
+    claims.push(claim);
+  }
+
+  let (w, h) = (max_width as usize, max_height as usize);
+  let mut grid: Vec<Vec<u32>> = vec![vec![0; w]; h];
+
+  for claim in &claims {
+    for j in claim.y..(claim.y + claim.height) {
+      for i in claim.x..(claim.x + claim.width) {
+        let (x, y) = (i as usize, j as usize);
+        grid[y][x] += 1;
+      }
+    }
+  }
+
+  let mut result = 0;
+  for j in 0..max_height as usize {
+    for i in 0..max_width as usize {
+      if grid[j][i] >= 2 {
+        result += 1;
+      }
+    }
+  }
+
+  println!("Result: {}", result);
+
+  // exercise 2
+  'claims: for claim in &claims {
+    for j in claim.y..(claim.y + claim.height) {
+      for i in claim.x..(claim.x + claim.width) {
+        let (x, y) = (i as usize, j as usize);
+        if grid[y][x] > 1 {
+          continue 'claims;
+        }
+      }
+    }
+
+    println!("Disjoint claim: {}", claim._id);
+  }
+}