From d5daf0de990f218349f1c9414990ec8347a1ef12 Mon Sep 17 00:00:00 2001
From: wieerwill <robert.jeutter@gmx.de>
Date: Wed, 6 Dec 2023 20:16:22 +0100
Subject: [PATCH] solve Day06 in Rust

---
 Day06/rust/Cargo.toml  |  8 +++++++
 Day06/rust/src/main.rs | 54 ++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 62 insertions(+)
 create mode 100644 Day06/rust/Cargo.toml
 create mode 100644 Day06/rust/src/main.rs

diff --git a/Day06/rust/Cargo.toml b/Day06/rust/Cargo.toml
new file mode 100644
index 0000000..1ec6963
--- /dev/null
+++ b/Day06/rust/Cargo.toml
@@ -0,0 +1,8 @@
+[package]
+name = "rust"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
diff --git a/Day06/rust/src/main.rs b/Day06/rust/src/main.rs
new file mode 100644
index 0000000..b537658
--- /dev/null
+++ b/Day06/rust/src/main.rs
@@ -0,0 +1,54 @@
+use std::fs::File;
+use std::io::{self, BufRead, BufReader};
+
+fn parse_input(file_path: &str) -> io::Result<(i64, i64)> {
+    let file = File::open(file_path)?;
+    let reader = BufReader::new(file);
+
+    let mut lines = reader.lines();
+    let time_line = lines.next().ok_or(io::Error::new(io::ErrorKind::Other, "Missing time line"))??;
+    let distance_line = lines.next().ok_or(io::Error::new(io::ErrorKind::Other, "Missing distance line"))??;
+
+    let time = time_line.chars().filter(|c| c.is_digit(10)).collect::<String>().parse::<i64>().unwrap_or(0);
+    let distance = distance_line.chars().filter(|c| c.is_digit(10)).collect::<String>().parse::<i64>().unwrap_or(0);
+
+    Ok((time, distance))
+}
+
+fn calculate_winning_ways(time: i64, record: i64) -> i64 {
+    let mut min_hold_time = 0;
+    while min_hold_time * (time - min_hold_time) <= record && min_hold_time < time {
+        min_hold_time += 1;
+    }
+    let mut max_hold_time = time - 1;
+    while max_hold_time * (time - max_hold_time) <= record && max_hold_time >= 0 {
+        max_hold_time -= 1;
+    }
+    std::cmp::max(0, max_hold_time - min_hold_time + 1)
+}
+
+fn run_test(file_path: &str, expected_result: i64) -> io::Result<()> {
+    let (time, distance) = parse_input(file_path)?;
+    let result = calculate_winning_ways(time, distance);
+    assert_eq!(result, expected_result, "Test failed! Expected {}, got {}", expected_result, result);
+    println!("Test passed successfully.");
+    Ok(())
+}
+
+fn main() {
+    let test_file_path = "../test.txt";
+    let expected_test_result = 71503; // Expected result from the test file
+    if let Err(e) = run_test(test_file_path, expected_test_result) {
+        eprintln!("An error occurred during test: {}", e);
+        return;
+    }
+
+    let input_file_path = "../input.txt";
+    match parse_input(input_file_path) {
+        Ok((time, distance)) => {
+            let result = calculate_winning_ways(time, distance);
+            println!("Final result from input file: {}", result);
+        }
+        Err(e) => eprintln!("An error occurred while processing input file: {}", e),
+    }
+}