Wrote program for Day 41

README.md

@@ -87,7 +87,7 @@ We encourage you to share your progress and ask questions in the Discussions sec
 | Day #38       | [Electronics Shop](https://github.com/LiveGray/100-Days-Of-Rust/tree/main/Week-06/Day-38_Electronics-Shop)                      | :white_check_mark:      |
 | Day #39       | [Halloween Sale](https://github.com/LiveGray/100-Days-Of-Rust/tree/main/Week-06/Day-39_Halloween-Sale)                        | :white_check_mark:      |
 | Day #40       | [Larrys Array](https://github.com/LiveGray/100-Days-Of-Rust/tree/main/Week-06/Day-40_Larrys-Array)                          | :white_check_mark:      |
-| Day #41       | [Sales By Match](https://github.com/LiveGray/100-Days-Of-Rust/tree/main/Week-06/Day-41_Sales-By-Match)                        | :white_large_square:      |
+| Day #41       | [Sales By Match](https://github.com/LiveGray/100-Days-Of-Rust/tree/main/Week-06/Day-41_Sales-By-Match)                        | :white_check_mark:      |
 | Day #42       | [Drawing Book](https://github.com/LiveGray/100-Days-Of-Rust/tree/main/Week-06/Day-42_Drawing-Book)                          | :white_large_square:      |
 | Day #43       | [Area Of A Triangle](https://github.com/LiveGray/100-Days-Of-Rust/tree/main/Week-07/Day-43_Area-Of-A-Triangle)                    | :white_large_square:      |
 | Day #44       | [Maximum Edge Of A Triangle](https://github.com/LiveGray/100-Days-Of-Rust/tree/main/Week-07/Day-44_Maximum-Edge-Of-A-Triangle)            | :white_large_square:      |

Week-06/Day-41_Sales-By-Match/day41/Cargo.toml

@@ -0,0 +1,6 @@
+[package]
+name = "day41"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]

Week-06/Day-41_Sales-By-Match/day41/src/lib.rs

@@ -0,0 +1,18 @@
+use std::collections::HashMap;
+
+pub fn socks_match(socks: &[usize]) -> usize {
+    let mut count: HashMap<&usize, usize> = HashMap::new();
+    let mut result = 0;
+
+    for sock in socks {
+        count.entry(sock).and_modify(|x| *x += 1).or_default();
+        if count[sock] == 2 {
+            result += 1;
+            if let Some(x) = count.get_mut(&sock) {
+                *x = 0;
+            }
+        }
+    }
+
+    result
+}

Week-06/Day-41_Sales-By-Match/day41/src/main.rs

@@ -0,0 +1,30 @@
+use std::{
+    io::{self, Write},
+    process::exit,
+};
+
+use day41::socks_match;
+
+fn main() {
+    print!("Please enter the colors of the socks as a list of numbers, separated by spaces: ");
+    io::stdout().flush().expect("Failed to flush stdout");
+
+    let mut buffer = String::new();
+    io::stdin()
+        .read_line(&mut buffer)
+        .expect("Failed to read line");
+
+    let socks: Vec<usize> = buffer
+        .split_whitespace()
+        .map(|x| match x.parse() {
+            Ok(x) => x,
+            Err(e) => {
+                eprintln!("{e}");
+                exit(1);
+            }
+        })
+        .collect();
+
+    let count = socks_match(&socks);
+    println!("The number of pairs is {count}.");
+}

Week-06/Day-41_Sales-By-Match/day41/tests/example.rs

@@ -0,0 +1,9 @@
+#[cfg(test)]
+mod example {
+    use day41::socks_match;
+
+    #[test]
+    fn test_example() {
+        assert_eq!(socks_match(&[1, 2, 1, 2, 1, 3, 2]), 2);
+    }
+}