diff --git a/Cargo.toml b/Cargo.toml
index cb8882f..c5f1c69 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -5,8 +5,12 @@ edition = "2021"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
+[profile.dev.package."*"] # +
+opt-level = "z"     # Optimize library for size
+
 [profile.release]
-opt-level = 'z'     # Optimize for size
+#opt-level = 'z'     # Optimize for size
+opt-level = 3       # Optimize for speed
 lto = true          # Enable link-time optimization
 codegen-units = 1   # Reduce number of codegen units to increase optimizations
 panic = 'abort'     # Abort on panic
@@ -14,5 +18,4 @@ strip = true        # Strip symbols from binary*
 
 [dependencies]
 text_io = "0.1.12"
-prettytable-rs = "0.10.0"
-tabled = "0.12.2"
\ No newline at end of file
+tabled = "0.14.0"
\ No newline at end of file
diff --git a/src/bit_utilities.rs b/src/bit_utilities.rs
index 068c3ad..349994d 100644
--- a/src/bit_utilities.rs
+++ b/src/bit_utilities.rs
@@ -1,4 +1,3 @@
-// use prettytable::{Cell, Row, Table};
 use std::collections::VecDeque;
 use std::{cmp, fmt};
 
@@ -11,9 +10,9 @@ fn capitalise(s: &str) -> String {
 }
 
 /// A basic register capable of storing binary data.
-#[derive(Debug)]
+#[derive(Debug, Clone)]
 pub struct BasicRegister {
-    /// A [Vec] that stores the binary data of the register.
+    /// A [VecDeque] that stores the binary data of the register.
     memory: VecDeque<bool>,
 }
 
@@ -43,39 +42,27 @@ impl BasicRegister {
     }
 
     /// Shifts the register to the left by a specified number of steps, shifting in the provided values.
-    pub fn left_shift(
-        &mut self,
-        shift_in_value_default: Option<bool>,
-        bits_shifted_default: Option<i32>,
-    ) -> VecDeque<bool> {
-        let shift_in_value: bool = shift_in_value_default.unwrap_or(false);
-        let bits_shifted: usize = bits_shifted_default.unwrap_or(1) as usize;
+    pub fn left_shifted(&self, shift_in_value: bool, bits_shifted: usize) -> Self {
+        let mut shifted_memory = self.memory.clone();
 
-        let mut shifted_bits: VecDeque<bool> = [].into();
-        for _i in 0..bits_shifted {
-            shifted_bits.push_back(self.memory.pop_front().unwrap());
-            self.memory.push_back(shift_in_value)
+        for _ in 0..bits_shifted {
+            shifted_memory.pop_front();
+            shifted_memory.push_back(shift_in_value)
         }
 
-        shifted_bits
+        BasicRegister::new(shifted_memory)
     }
 
     /// Shifts the register to the left by a specified number of steps, shifting in the provided values.
-    pub fn right_shift(
-        &mut self,
-        shift_in_value_default: Option<bool>,
-        bits_shifted_default: Option<i32>,
-    ) -> VecDeque<bool> {
-        let shift_in_value: bool = shift_in_value_default.unwrap_or(false);
-        let bits_shifted: usize = bits_shifted_default.unwrap_or(1) as usize;
+    pub fn right_shifted(&self, shift_in_value: bool, bits_shifted: i32) -> Self {
+        let mut shifted_memory = self.memory.clone();
 
-        let mut shifted_bits: VecDeque<bool> = [].into();
         for _i in 0..bits_shifted {
-            shifted_bits.push_back(self.memory.pop_back().unwrap());
-            self.memory.push_front(shift_in_value)
+            shifted_memory.pop_back();
+            shifted_memory.push_front(shift_in_value)
         }
 
-        shifted_bits
+        BasicRegister::new(shifted_memory)
     }
 
     /// Constructs a new BasicRegister from a given VecDeque<bool> as memory.
@@ -104,6 +91,20 @@ impl BasicRegister {
 
         builder.build().with(Style::modern()).to_string()
     }
+
+    fn decrement(&mut self) {
+        let one = BasicRegister::new([true].into()).adjusted_by_size(self.len());
+        self.memory = binary_subtraction(self, &one).memory;
+    }
+
+    fn increment(&mut self) {
+        let one = BasicRegister::new([true].into()).adjusted_by_size(self.len());
+        self.memory = binary_sum(self, &one).memory;
+    }
+
+    fn non_zero(&mut self) -> bool {
+        self.memory.iter().any(|i| *i)
+    }
 }
 
 impl Default for BasicRegister {
@@ -234,3 +235,32 @@ pub fn binary_subtraction(minuend: &BasicRegister, subtrahend: &BasicRegister) -
         false => difference.negated(),
     }
 }
+
+/// Multiplies the first term by the second term.
+pub fn binary_multiplication_method_1(
+    first_term: &BasicRegister,
+    second_term: &BasicRegister,
+) -> BasicRegister {
+    let n = first_term.len();
+    let mut rg1: BasicRegister = BasicRegister::new(vec![false; n].into());
+    let mut rg2: &BasicRegister = first_term;
+    let rg3: &BasicRegister = second_term;
+    let mut counter: BasicRegister = BasicRegister::new(char_to_bool_vecdeque(format!("{n:b}").chars().collect()));
+
+    let _i = 0;
+
+    while counter.non_zero() {
+        let value_to_check = rg2.memory[n - 1].clone();
+        if value_to_check {
+            rg1 = binary_sum(&rg1, rg3);
+        }
+
+        let new_rg2 = rg2.right_shifted(rg1.memory[n - 1], 1).clone();
+        rg2 = &rg2.right_shifted(rg1.memory[n - 1], 1);
+        rg1 = rg1.right_shifted(false, 1);
+        counter.decrement();
+    }
+
+    rg1.memory.append(&mut rg2.memory.clone());
+    rg1
+}
diff --git a/src/main.rs b/src/main.rs
index e79c143..f289f4d 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,15 +1,19 @@
-#[allow(dead_code)]
+#![allow(dead_code)]
+
 mod bit_utilities;
 
 use bit_utilities as bu;
 use text_io::read;
 
-fn input_handler(first_register: bu::BasicRegister, second_register: bu::BasicRegister) {
-    let (first_register, second_register) = bu::align_registers(first_register, second_register);
+fn input_handler() {
+    let (mut first_register, mut second_register) = bu::align_registers(
+        bu::BasicRegister::new(bu::get_memory("first number")),
+        bu::BasicRegister::new(bu::get_memory("second number")),
+    );
 
-    println!();
-    println!("First register:\n{}", first_register.table());
-    println!("Second register:\n{}", second_register.table());
+    // println!();
+    // println!("First register:\n{}", first_register.table());
+    // println!("Second register:\n{}", second_register.table());
 
     loop {
         print!("\nChoose the operation:\n[a]ddition, [s]ubtraction, [m]ultiplication, [d]ivision, [q]uit\n>>> ");
@@ -20,10 +24,24 @@ fn input_handler(first_register: bu::BasicRegister, second_register: bu::BasicRe
                 println!("Sum:\n{}\nResult (to copy): {sum:b}", sum.table())
             }
             "s" => {
-                let difference: bu::BasicRegister = bu::binary_subtraction(&first_register, &second_register);
-                println!("Difference:\n{}\nResult (to copy): {difference:b}", difference.table())
-            }
-            "m" => (),
+                let difference: bu::BasicRegister =
+                    bu::binary_subtraction(&first_register, &second_register);
+                println!(
+                    "Difference:\n{}\nResult (to copy): {difference:b}",
+                    difference.table()
+                )
+            },
+            "m" => loop {
+                print!("\nChoose method to use (1-4): ");
+                let method_input: String = read!();
+                match method_input.as_str() {
+                    "1" => {
+                        println!("{}", bu::binary_multiplication_method_1(&first_register, &second_register));
+                        break;
+                    },
+                    _ => println!("Not an available operation, try again."),
+                }
+            },
             "d" => (),
             "q" => std::process::exit(0x0100),
             _ => println!("Not an available operation, try again."),
@@ -32,8 +50,11 @@ fn input_handler(first_register: bu::BasicRegister, second_register: bu::BasicRe
 }
 
 fn main() {
-    let reg = bu::BasicRegister::new(bu::get_memory("your number"));
-    let reg2 = bu::BasicRegister::new(bu::get_memory("your number"));
-
-    input_handler(reg, reg2);
+    // let mut reg = bu::BasicRegister::new(bu::get_memory("your number"));
+    // let mut reg2 = bu::BasicRegister::new(bu::get_memory("your number"));
+    //
+    // println!("{reg}");
+    // println!("{reg2}");
+    // println!("{}", bu::binary_multiplication_method_1(reg, reg2))
+    input_handler();
 }