Advent 2023 Day 1

advent_of_code_2023/day1/main1.rs

@@ -0,0 +1,25 @@
+use std::fs::read_to_string;
+
+fn main() {
+    let mut calibration = 0;
+
+    for line in read_to_string("input.txt").unwrap().lines() {
+        let mut first = 0;
+        let mut last = 0;
+        let mut set_first = false;
+
+        for char in line.chars() {
+            if char.is_ascii_digit() {
+                if !set_first {
+                    first = char as i32 - '0' as i32;
+                    set_first = true;
+                }
+                last = char as i32 - '0' as i32;
+            }
+        }
+
+        calibration += 10 * first + last;
+    }
+
+    println!("{}", calibration);
+}

advent_of_code_2023/main2.rs

@@ -0,0 +1,112 @@
+use std::fs::read_to_string;
+use std::vec::Vec;
+
+fn inline_compare(line: &str, caret: usize, word: &str) -> bool {
+    for idx in 0..word.len() {
+        if (caret + idx)  == line.len() {
+            return false
+        }
+
+        if line.as_bytes()[caret + idx] != word.as_bytes()[idx] {
+            return false
+        }
+
+        // 3rd case: line is long enough and characters match
+    }
+
+    true
+}
+
+fn parse_to_numbers(line: &str) -> Vec<i32> {
+    let mut rval: Vec<i32> = Vec::new();
+    
+    /*
+        one
+        eight
+        nine
+
+        four
+        five
+
+        two
+        three
+
+        six
+        seven
+    */
+
+    let slice = line.as_bytes();
+    for idx in 0..line.len() {
+        match slice[idx] {
+            b'0'..=b'9' => rval.push(slice[idx] as i32 - '0' as i32),
+            
+            b'o' => {
+                if inline_compare(line, idx, "one") {
+                    rval.push(1);
+                }
+            }
+
+            b'e' => {
+                if inline_compare(line, idx, "eight") {
+                    rval.push(8);
+                }
+            }
+
+            b'n' => {
+                if inline_compare(line, idx, "nine") {
+                    rval.push(9);
+                }
+            }
+
+            b'f' => {
+                if inline_compare(line, idx, "four") {
+                    rval.push(4);
+                } else if inline_compare(line, idx, "five") {
+                    rval.push(5);
+                }
+            }
+
+            b't' => {
+                if inline_compare(line, idx, "two") {
+                    rval.push(2);
+                } else if inline_compare(line, idx, "three") {
+                    rval.push(3);
+                }
+            }
+
+            b's' => {
+                if inline_compare(line, idx, "six") {
+                    rval.push(6);
+                } else if inline_compare(line, idx, "seven") {
+                    rval.push(7);
+                }
+            }
+            _ => ()
+        }
+    }
+
+    return rval;
+}
+
+fn main() {
+    let mut calibration = 0;
+
+    for line in read_to_string("input.txt").unwrap().lines() {
+        let numbers = parse_to_numbers(line);
+        println!{"{:?}", numbers}
+
+        let first = match numbers.first() {
+            Some(n) => n,
+            None => continue
+        };
+
+        let last = match numbers.last() {
+            Some(n) => n,
+            None => continue
+        };
+
+        calibration += 10 * first + last;
+    }
+
+    println!("{}", calibration);
+}