Implement 2025 - Day 2 - Part 1

2025/02.rs

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+---cargo
+---
+
+static CONTENT: &'static str = include_str!("./inputs/02_1.txt");
+
+fn main() {
+    let ranges: Vec<_> = CONTENT.split(',').map(|l| l.trim()).filter(|l| !l.is_empty()).map(|l| {
+        let (raw_start, raw_end) = l.split_once('-').unwrap();
+        let start: usize = raw_start.parse().unwrap();
+        let end: usize = raw_end.parse().unwrap();
+
+        start..=end
+    }).collect();
+
+    println!("Ranges: {:?}", ranges);
+
+    let mut result = 0;
+    for r in ranges.iter() {
+        for v in r.clone() {
+            let len = v.ilog10() + 1;
+            if len % 2 != 0 {
+                continue;
+            }
+
+            let first_half = v / 10_usize.pow(len/2);
+            let second_half = v - (first_half * 10_usize.pow(len/2));
+
+            if first_half == second_half {
+                result += v;
+                println!("Invalid {} - Halves ({}, {})", v, first_half, second_half);
+            }
+        }
+    }
+
+    println!("Result: {}", result);
+}

2025/inputs/02_1.txt

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+17330-35281,9967849351-9967954114,880610-895941,942-1466,117855-209809,9427633930-9427769294,1-14,311209-533855,53851-100089,104-215,33317911-33385573,42384572-42481566,43-81,87864705-87898981,258952-303177,451399530-451565394,6464564339-6464748782,1493-2439,9941196-10054232,2994-8275,6275169-6423883,20-41,384-896,2525238272-2525279908,8884-16221,968909030-969019005,686256-831649,942986-986697,1437387916-1437426347,8897636-9031809,16048379-16225280

2025/inputs/02_example.txt

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+11-22,95-115,998-1012,1188511880-1188511890,222220-222224,1698522-1698528,446443-446449,38593856-38593862,565653-565659,824824821-824824827,2121212118-2121212124