diff --git a/duplicates/src/main.rs b/duplicates/src/main.rs
index a55267a..f7287c2 100644
--- a/duplicates/src/main.rs
+++ b/duplicates/src/main.rs
@@ -14,9 +14,7 @@
  * Licensed under the GPLv2 License, Version 2.0 (the "License");
  * Copyright (c) Sven Vogel
  */
-
 use crate::FloatOrChar::{Char, Float};
-use std::collections::{HashMap, HashSet};
 use std::fmt::Debug;
 use std::usize;
 
diff --git a/fibonacci/src/main.rs b/fibonacci/src/main.rs
index 9551b6e..8f625c2 100644
--- a/fibonacci/src/main.rs
+++ b/fibonacci/src/main.rs
@@ -16,6 +16,7 @@
  */
 
 /// recursive variant of the fibonacci function
+#[allow(dead_code)]
 fn fib_rec(x: u128) -> u128 {
     if x < 2 {
         return x;
@@ -29,7 +30,7 @@ fn fib_loop(x: u128) -> u128 {
     let mut sum = 0;
     let mut sum2 = 1;
 
-    for x in 0..(x - 1) {
+    for _ in 0..(x - 1) {
         let t = sum;
         sum = sum2;
         sum2 = t + sum;
diff --git a/line/Cargo.toml b/line/Cargo.toml
new file mode 100644
index 0000000..8d42634
--- /dev/null
+++ b/line/Cargo.toml
@@ -0,0 +1,8 @@
+[package]
+name = "line"
+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/line/src/main.rs b/line/src/main.rs
new file mode 100644
index 0000000..837a7cc
--- /dev/null
+++ b/line/src/main.rs
@@ -0,0 +1,96 @@
+/**
+ *                _ _   _               _
+ * __      ___ __(_) |_| |_ ___ _ __   | |__  _   _
+ * \ \ /\ / / '__| | __| __/ _ \ '_ \  | '_ \| | | |
+ *  \ V  V /| |  | | |_| ||  __/ | | | | |_) | |_| |
+ *   \_/\_/ |_|  |_|\__|\__\___|_| |_| |_.__/ \__, |
+ *                                            |___/
+ *  ____                  __     __               _
+ * / ___|_   _____ _ __   \ \   / /__   __ _  ___| |
+ * \___ \ \ / / _ \ '_ \   \ \ / / _ \ / _` |/ _ \ |
+ *  ___) \ V /  __/ | | |   \ V / (_) | (_| |  __/ |
+ * |____/ \_/ \___|_| |_|    \_/ \___/ \__, |\___|_|
+ *                                     |___/
+ * Licensed under the GPLv2 License, Version 2.0 (the "License");
+ * Copyright (c) Sven Vogel
+ */
+use std::cmp::PartialOrd;
+use std::ops::{Add, Div, Mul, Sub};
+
+trait Calculate:
+    Mul<Output = Self> + Add<Output = Self> + Sub<Output = Self> + Div<Output = Self> + Copy
+{
+}
+
+impl<T> Calculate for T where
+    T: Mul<Output = Self> + Add<Output = Self> + Sub<Output = Self> + Div<Output = Self> + Copy
+{
+}
+
+struct Point<T: Mul<Output = T> + Add<Output = T> + Copy> {
+    x: T,
+    y: T,
+}
+
+#[allow(dead_code)]
+impl<T: Mul<Output = T> + Add<Output = T> + Copy> Point<T> {
+    fn squared_dist_to_0(&self) -> T {
+        self.x * self.x + self.y * self.y
+    }
+}
+
+trait MeasureDistanceTo0<T: Calculate> {
+    fn squared_dist_to_0(&self) -> T;
+}
+
+struct Line<T: Calculate> {
+    p: Point<T>,
+    n: Point<T>,
+}
+
+impl<T: Calculate + Default> MeasureDistanceTo0<T> for Line<T> {
+    fn squared_dist_to_0(&self) -> T {
+        let len = self.n.x * self.n.x + self.n.y * self.n.y;
+        let normalized = Point {
+            x: self.n.x / len,
+            y: self.n.y / len,
+        };
+
+        normalized.x * self.p.x + normalized.y * self.p.y
+    }
+}
+
+impl<T: Calculate + Default> Line<T> {
+    pub fn new() -> Self {
+        Self {
+            p: Point {
+                x: Default::default(),
+                y: Default::default(),
+            },
+            n: Point {
+                x: Default::default(),
+                y: Default::default(),
+            },
+        }
+    }
+}
+
+fn longest_dist_to_0<T>(p1: Line<T>, p2: Line<T>) -> T
+where
+    T: Calculate + Default + PartialOrd,
+{
+    let d1 = p1.squared_dist_to_0();
+    let d2 = p2.squared_dist_to_0();
+    if d1 > d2 {
+        d1
+    } else {
+        d2
+    }
+}
+
+fn main() {
+    let l0: Line<f64> = Line::new();
+    let l1: Line<f64> = Line::new();
+
+    println!("{:?}", longest_dist_to_0(l0, l1));
+}
diff --git a/tuple_arithmetic/src/main.rs b/tuple_arithmetic/src/main.rs
index 64c5249..432f1b6 100644
--- a/tuple_arithmetic/src/main.rs
+++ b/tuple_arithmetic/src/main.rs
@@ -28,6 +28,7 @@ fn merge_tuple(a: (f64, f64), b: (f64, f64), f: fn(a: f64, b: f64) -> f64) -> (f
     (f(a.0, b.0), f(a.1, b.1))
 }
 
+#[allow(dead_code)]
 fn add_tuple(a: (f64, f64), b: (f64, f64)) -> (f64, f64) {
     merge_tuple(a, b, |a, b| a + b)
 }