2 files changed, 143 insertions, 0 deletions
diff --git a/04/Cargo.toml b/04/Cargo.toml
new file mode 100644
index 0000000..00ee1d2
--- /dev/null
+++ b/04/Cargo.toml
@@ -0,0 +1,9 @@
+[package]
+name = "advent_04"
+version = "0.1.0"
+authors = ["Irene Knapp <ireneista@gmail.com>"]
+edition = "2018"
+
+[dependencies]
+advent_lib = { path = "../lib" }
+regex = "1"
diff --git a/04/src/main.rs b/04/src/main.rs
new file mode 100644
index 0000000..701f60d
--- /dev/null
+++ b/04/src/main.rs
@@ -0,0 +1,134 @@
+use advent_lib::prelude::*;
+
+use regex::Regex;
+use std::collections::BTreeSet;
+
+
+fn main() -> Result<()> {
+  let mut args = std::env::args();
+  if args.len() != 2 {
+    eprintln!("Usage: advent input");
+  }
+  let _ = args.next();
+  let filename = args.next().unwrap();
+
+  let input = advent_lib::read_lines_file(&filename)?;
+
+  let overall_regex = Regex::new(r"([a-z][a-z][a-z]):([^ \n]*)").unwrap();
+  let year_regex = Regex::new(r"^[0-9][0-9][0-9][0-9]$").unwrap();
+  let height_regex = Regex::new(r"^([0-9]+)(cm|in)$").unwrap();
+  let rgb_regex = Regex::new(r"^#[0-9a-f][0-9a-f][0-9a-f][0-9a-f][0-9a-f][0-9a-f]$").unwrap();
+  let eye_regex = Regex::new(r"^(amb|blu|brn|gry|grn|hzl|oth)$").unwrap();
+  let id_regex = Regex::new(r"^[0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9]$").unwrap();
+
+  let mut n_valid: i64 = 0;
+  let mut current_fields: BTreeSet<String> = BTreeSet::new();
+  let mut current_is_valid = true;
+
+  for line in &input {
+    if line.trim().len() == 0 {
+      //println!("{:?}", current_fields);
+
+      if current_is_valid
+        && current_fields.contains("byr")
+        && current_fields.contains("iyr")
+        && current_fields.contains("eyr")
+        && current_fields.contains("hgt")
+        && current_fields.contains("hcl")
+        && current_fields.contains("ecl")
+        && current_fields.contains("pid") {
+        n_valid += 1;
+      }
+
+      current_fields = BTreeSet::new();
+      current_is_valid = true;
+    }
+
+    for captures in overall_regex.captures_iter(line) {
+      let mut field_name = String::new();
+      field_name.push_str(&captures[1]);
+
+      let mut field_value = String::new();
+      field_value.push_str(&captures[2]);
+
+      current_fields.insert(field_name);
+
+      match &captures[1] {
+        "byr" => {
+          if year_regex.is_match(&field_value) {
+            let year = field_value.parse::<i64>()?;
+            if year < 1920 || year > 2002 {
+              current_is_valid = false;
+            }
+          } else {
+            current_is_valid = false;
+          }
+        },
+        "iyr" => {
+          if year_regex.is_match(&field_value) {
+            let year = field_value.parse::<i64>()?;
+            if year < 2010 || year > 2020 {
+              current_is_valid = false;
+            }
+          } else {
+            current_is_valid = false;
+          }
+        },
+        "eyr" => {
+          if year_regex.is_match(&field_value) {
+            let year = field_value.parse::<i64>()?;
+            if year < 2020 || year > 2030 {
+              current_is_valid = false;
+            }
+          } else {
+            current_is_valid = false;
+          }
+        },
+        "hgt" => {
+          if height_regex.is_match(&field_value) {
+            let captures = height_regex.captures(&field_value).unwrap();
+            let number = captures[1].parse::<i64>()?;
+
+            match &captures[2] {
+              "cm" => {
+                if number < 150 || number > 193 {
+                  current_is_valid = false;
+                }
+              },
+              "in" => {
+                if number < 59 || number > 76 {
+                  current_is_valid = false;
+                }
+              },
+              _ => { },
+            }
+          } else {
+            current_is_valid = false;
+          }
+        },
+        "hcl" => {
+          if !rgb_regex.is_match(&field_value) {
+            current_is_valid = false;
+          }
+        },
+        "ecl" => {
+          if !eye_regex.is_match(&field_value) {
+            current_is_valid = false;
+          }
+        },
+        "pid" => {
+          if !id_regex.is_match(&field_value) {
+            current_is_valid = false;
+          }
+        },
+        _ => {
+        },
+      };
+    }
+    //println!("end of line");
+  }
+
+  println!("{}", n_valid);
+
+  Ok(())
+}