2015 day 8

2015/src/bin/day8.rs

@@ -0,0 +1,40 @@
+use aoc::input;
+
+fn main() {
+    let lines = input::read_lines();
+
+    // Part 1
+    let mut used_mem = 0;
+    let mut num_chars = 0;
+    for line in &lines {
+        let chars = line.chars().collect::<Vec<char>>();
+        let line_mem = chars.len();
+        let mut line_num_chars = line_mem - 2;
+        let mut index = 1;
+        while index < line_mem - 1 {
+            if chars[index] == '\\' {
+                if chars[index + 1] == '"' || chars[index + 1] == '\\' {
+                    line_num_chars -= 1;
+                    index += 1;
+                } else if chars[index + 1] == 'x' {
+                    line_num_chars -= 3;
+                    index += 3;
+                }
+            }
+            index += 1;
+        }
+        used_mem += line_mem;
+        num_chars += line_num_chars;
+    }
+    println!("{} - {} = {}", used_mem, num_chars, used_mem - num_chars);
+
+    // Part 2
+    let mut encoded_size = used_mem;
+    for line in &lines {
+        for c in line.chars() {
+            if c == '\\' || c == '"' { encoded_size += 1 }
+        }
+        encoded_size += 2; // enclosing quotes
+    }
+    println!("{} - {} = {}", encoded_size, used_mem, encoded_size - used_mem);
+}