day_3: rust solution

day_3/rust/Cargo.toml

@@ -0,0 +1,8 @@
+[package]
+name = "day_3_rust"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]

day_3/rust/src/main.rs

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+const CHARS_COUNT: usize = 52;
+type AppearCharArray = [bool; CHARS_COUNT];
+
+fn convert_ascii(ascii_char: u8) -> usize {
+	if ascii_char > 96 && ascii_char < 123 {
+		return (ascii_char - 96) as usize;
+	}
+
+	if ascii_char > 64 && ascii_char < 91 {
+		return (ascii_char - 38) as usize;
+	}
+
+	panic!("Cannot parse '{ascii_char};");
+}
+
+fn get_appear_arr(string: &str) -> AppearCharArray {
+	let mut store: AppearCharArray = [false; CHARS_COUNT];
+
+	for byte in string.bytes() {
+		let parsed_char = convert_ascii(byte);
+
+		if !store[parsed_char - 1] {
+			store[parsed_char - 1] = true;
+		}
+	}
+
+	return store;
+}
+
+fn get_appear_sum(unique_chars_arrays: Vec<AppearCharArray>) -> [u8; CHARS_COUNT] {
+	let mut result: [u8; CHARS_COUNT] = [0; 52];
+
+	for index in 0..CHARS_COUNT {
+		let mut sum: u8 = 0;
+
+		for array_index in 0..unique_chars_arrays.len() {
+			sum += unique_chars_arrays[array_index][index] as u8;
+		}
+
+		result[index] = sum;
+	}
+
+	return result;
+}
+
+fn get_appear_chars_sum(array: [u8; CHARS_COUNT], number: u8) -> i32 {
+	let mut sum: i32 = 0;
+
+	for (index, num) in array.into_iter().enumerate() {
+		if num == number {
+			sum += index as i32 + 1;
+		}
+	}
+
+	return sum;
+}
+
+fn main() {
+	let data = include_str!("../../input.txt");
+
+	let mut iter = data.lines();
+	let mut sum: i32 = 0;
+
+	loop {
+		let lines = match (iter.next(), iter.next(), iter.next()) {
+			(Some(a), Some(b), Some(c)) => [a, b, c],
+			_ => break,
+		};
+
+		let appears = Vec::from(lines.map(|line| get_appear_arr(line)));
+
+		let chars_sum = get_appear_chars_sum(get_appear_sum(appears), lines.len() as u8);
+		sum += chars_sum;
+	}
+
+	// let sum: i32 = data
+	// 	.lines()
+	// 	.map(|line| {
+	// 		let (left, right) = line.split_at(line.len() / 2);
+
+	// 		let appears = vec![get_appear_arr(left), get_appear_arr(right)];
+
+	// 		return get_appear_chars_sum(get_appear_sum(appears), 2);
+	// 	})
+	// 	.sum();
+
+	println!("{sum}");
+}