2016/16

2016/16/Cargo.lock

@@ -0,0 +1,4 @@
+[root]
+name = "16"
+version = "0.1.0"
+

2016/16/Cargo.toml

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+[package]
+name = "16"
+version = "0.1.0"
+authors = ["logaritmisk <anders.e.olsson@gmail.com>"]
+
+[dependencies]

2016/16/src/main.rs

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+pub fn generate_data(input: &str) -> String {
+    let mut data = input.to_owned();
+
+    data.push('0');
+
+    for c in input.chars().rev() {
+        data.push(if c == '0' { '1' } else { '0' });
+    }
+
+    data
+}
+
+pub fn calculate_checksum(input: &str) -> String {
+    let mut data = String::new();
+
+    for pair in input.as_bytes().chunks(2) {
+        data.push(if pair[0] == pair[1] { '1' } else { '0' })
+    }
+
+    data
+}
+
+pub fn fill_disk(state: &str, length: usize) -> (String, String) {
+    let mut state = state.to_owned();
+
+    while state.len() < length {
+        state = generate_data(&state);
+    }
+
+    state.truncate(length);
+
+    let mut checksum = calculate_checksum(&state);
+
+    while checksum.len() % 2 == 0 {
+        checksum = calculate_checksum(&checksum);
+    }
+
+    (state, checksum)
+}
+
+
+fn main() {
+    let data = fill_disk("01110110101001000", 272);
+
+    println!("checksum_1={}", data.1);
+
+    let data = fill_disk("01110110101001000", 35651584);
+
+    println!("checksum_2={}", data.1);
+}
+
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn example_01() {
+        assert_eq!("100".to_owned(), generate_data("1"));
+    }
+
+    #[test]
+    fn example_02() {
+        assert_eq!("001".to_owned(), generate_data("0"));
+    }
+
+    #[test]
+    fn example_03() {
+        assert_eq!("11111000000".to_owned(), generate_data("11111"));
+    }
+
+    #[test]
+    fn example_04() {
+        assert_eq!("1111000010100101011110000".to_owned(), generate_data("111100001010"));
+    }
+
+    #[test]
+    fn example_05() {
+        assert_eq!("110101".to_owned(), calculate_checksum("110010110100"));
+        assert_eq!("100".to_owned(), calculate_checksum("110101"));
+    }
+}