diff --git a/2023/day3/day3/.gitignore b/2023/day3/day3/.gitignore
new file mode 100644
index 0000000..ea8c4bf
--- /dev/null
+++ b/2023/day3/day3/.gitignore
@@ -0,0 +1 @@
+/target
diff --git a/2023/day3/day3/Cargo.lock b/2023/day3/day3/Cargo.lock
new file mode 100644
index 0000000..c149834
--- /dev/null
+++ b/2023/day3/day3/Cargo.lock
@@ -0,0 +1,54 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 3
+
+[[package]]
+name = "aho-corasick"
+version = "1.1.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b2969dcb958b36655471fc61f7e416fa76033bdd4bfed0678d8fee1e2d07a1f0"
+dependencies = [
+ "memchr",
+]
+
+[[package]]
+name = "day3"
+version = "0.1.0"
+dependencies = [
+ "regex",
+]
+
+[[package]]
+name = "memchr"
+version = "2.6.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f665ee40bc4a3c5590afb1e9677db74a508659dfd71e126420da8274909a0167"
+
+[[package]]
+name = "regex"
+version = "1.10.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "380b951a9c5e80ddfd6136919eef32310721aa4aacd4889a8d39124b026ab343"
+dependencies = [
+ "aho-corasick",
+ "memchr",
+ "regex-automata",
+ "regex-syntax",
+]
+
+[[package]]
+name = "regex-automata"
+version = "0.4.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5f804c7828047e88b2d32e2d7fe5a105da8ee3264f01902f796c8e067dc2483f"
+dependencies = [
+ "aho-corasick",
+ "memchr",
+ "regex-syntax",
+]
+
+[[package]]
+name = "regex-syntax"
+version = "0.8.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c08c74e62047bb2de4ff487b251e4a92e24f48745648451635cec7d591162d9f"
diff --git a/2023/day3/day3/Cargo.toml b/2023/day3/day3/Cargo.toml
new file mode 100644
index 0000000..3c9ca88
--- /dev/null
+++ b/2023/day3/day3/Cargo.toml
@@ -0,0 +1,9 @@
+[package]
+name = "day3"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+regex = "1.10.2"
diff --git a/2023/day3/day3/input.txt b/2023/day3/day3/input.txt
new file mode 100644
index 0000000..cab8523
--- /dev/null
+++ b/2023/day3/day3/input.txt
@@ -0,0 +1,141 @@
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+
diff --git a/2023/day3/day3/inputTest.txt b/2023/day3/day3/inputTest.txt
new file mode 100644
index 0000000..b20187f
--- /dev/null
+++ b/2023/day3/day3/inputTest.txt
@@ -0,0 +1,10 @@
+467..114..
+...*......
+..35..633.
+......#...
+617*......
+.....+.58.
+..592.....
+......755.
+...$.*....
+.664.598..
diff --git a/2023/day3/day3/script.py b/2023/day3/day3/script.py
new file mode 100644
index 0000000..212d84f
--- /dev/null
+++ b/2023/day3/day3/script.py
@@ -0,0 +1,43 @@
+import re
+from collections import defaultdict
+
+
+f = open("inputTest.txt", "r")
+
+lines = f.read().splitlines()
+outputSum = 0
+outputSumP2 = 0
+
+# Dictionary of adjacent numbers with a list as default value
+adjacent = defaultdict(list)
+
+for i, line in enumerate(lines):
+    for match in re.finditer(r"\d+", line):
+        indexes = [(i, match.start() - 1), (i, match.end())]
+        for k in range(match.start() - 1, match.end() + 1):
+            indexes.append((i - 1, k))
+            indexes.append((i + 1, k))
+
+        for index1, index2 in indexes:
+            # Check if the index is within the bounds of the list
+            if index1 >= 0 and index1 < len(lines):
+                if index2 >= 0 and index2 < len(lines[index1]):
+                    # Check if the character is not "whitespace"
+                    if lines[index1][index2] != ".":
+                        # Add the number to the output
+                        outputSum += int(match.group())
+
+                        # Part 2
+                        # Append number to the adjacency list
+                        adjacent[index1, index2].append(int(match.group()))
+
+                        break
+
+# Part 2
+for val in adjacent.values():
+    if len(val) == 2:
+        outputSumP2 += int(val[0]) * int(val[1])
+
+print(outputSum)
+print(outputSumP2)
+
diff --git a/2023/day3/day3/src/main.rs b/2023/day3/day3/src/main.rs
new file mode 100644
index 0000000..a060050
--- /dev/null
+++ b/2023/day3/day3/src/main.rs
@@ -0,0 +1,61 @@
+use std::collections::HashMap;
+use std::fs;
+
+fn main() {
+    let content = fs::read_to_string("inputTest.txt").expect("Could not read file");
+    let lines: Vec<&str> = content.lines().collect();
+
+    let mut output_sum = 0;
+    let mut output_sum_p2 = 0;
+
+    // Hashmap with a list of adjacent numbers
+    let mut adjacent: HashMap<(usize, usize), Vec<i32>> = HashMap::new();
+
+    // Create regex automaton outside of the loop for better performance
+    let regex = regex::Regex::new(r"\d+").unwrap();
+
+    for (i, line) in lines.iter().enumerate() {
+        for cap in regex.find_iter(line) {
+            let match_str = &line[cap.start()..cap.end()];
+            let num = match_str.parse::<i32>().unwrap();
+            let mut indexes = vec![(i, cap.start().saturating_sub(1)), (i, cap.end())];
+
+            for k in cap.start().saturating_sub(1)..=cap.end() {
+                indexes.push((i.saturating_sub(1), k));
+                indexes.push((i + 1, k));
+            }
+
+            for (index1, index2) in indexes {
+                if let Some(line) = lines.get(index1) {
+                    if index2 < lines[index1].len() {
+                        if let Some(character) = line.chars().nth(index2) {
+                            if character != '.' {
+                                output_sum += num;
+
+                                // Part 2
+                                // Append the number to the adjacency list
+                                // If no element is found in the hashmap, create it first
+                                if let Some(adj) = adjacent.get_mut(&(index1, index2)) {
+                                    adj.push(num);
+                                } else {
+                                    adjacent.insert((index1, index2), vec![num]);
+                                }
+
+                                break;
+                            }
+                        }
+                    }
+                }
+            }
+        }
+    }
+
+    for val in adjacent.values() {
+        if val.len() == 2 {
+            output_sum_p2 += val[0] * val[1];
+        }
+    }
+
+    println!("{}", output_sum);
+    println!("{}", output_sum_p2);
+}