Wrote program for Day 39

README.md

@@ -85,7 +85,7 @@ We encourage you to share your progress and ask questions in the Discussions sec
 | Day #36       | [LCD Display](https://github.com/LiveGray/100-Days-Of-Rust/tree/main/Week-06/Day-36_LCD-Display)                           | :white_check_mark:      |
 | Day #37       | [Breaking The Records](https://github.com/LiveGray/100-Days-Of-Rust/tree/main/Week-06/Day-37_Breaking-The-Records)                  | :white_check_mark:      |
 | 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_large_square:      |
+| 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_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_large_square:      |
 | Day #42       | [Drawing Book](https://github.com/LiveGray/100-Days-Of-Rust/tree/main/Week-06/Day-42_Drawing-Book)                          | :white_large_square:      |

Week-06/Day-39_Halloween-Sale/day39/Cargo.toml

@@ -0,0 +1,6 @@
+[package]
+name = "day39"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]

Week-06/Day-39_Halloween-Sale/day39/src/lib.rs

@@ -0,0 +1,15 @@
+pub fn how_many_games(price: usize, discount: usize, min_price: usize, budget: usize) -> usize {
+    let mut games = 0;
+    let mut spent = 0;
+
+    while min_price < price - std::cmp::min(price, discount * games) {
+        spent += price - std::cmp::min(price, discount * games);
+        games += 1;
+    }
+
+    if min_price >= price - std::cmp::min(price, discount * games) {
+        games += (budget - spent) / min_price;
+    }
+
+    games
+}

Week-06/Day-39_Halloween-Sale/day39/src/main.rs

@@ -0,0 +1,55 @@
+use std::process::exit;
+
+use std::{
+    io::{self, Write},
+    num::ParseIntError,
+};
+
+use day39::how_many_games;
+
+fn read_usize(request: &str) -> Result<usize, ParseIntError> {
+    let mut buffer = String::new();
+
+    print!("{request}");
+    io::stdout().flush().expect("Failed to flush stdout");
+
+    io::stdin()
+        .read_line(&mut buffer)
+        .expect("Failed to read line");
+
+    buffer.trim().parse()
+}
+
+fn main() {
+    let price = match read_usize("Insert the normal price: ") {
+        Ok(x) => x,
+        Err(e) => {
+            eprintln!("{e}");
+            exit(1);
+        }
+    };
+    let discount = match read_usize("Insert the discount: ") {
+        Ok(x) => x,
+        Err(e) => {
+            eprintln!("{e}");
+            exit(1);
+        }
+    };
+    let min_price = match read_usize("Insert the minimum price: ") {
+        Ok(x) => x,
+        Err(e) => {
+            eprintln!("{e}");
+            exit(1);
+        }
+    };
+    let budget = match read_usize("Insert the budget: ") {
+        Ok(x) => x,
+        Err(e) => {
+            eprintln!("{e}");
+            exit(1);
+        }
+    };
+
+    let result = how_many_games(price, discount, min_price, budget);
+    println!("You can buy {result} games!");
+}

Week-06/Day-39_Halloween-Sale/day39/tests/example.rs

@@ -0,0 +1,9 @@
+#[cfg(test)]
+mod example {
+    use day39::how_many_games;
+
+    #[test]
+    fn example() {
+        assert_eq!(how_many_games(20, 3, 6, 80), 6);
+    }
+}