src/day5/mod.rs

@@ -121,41 +121,34 @@ pub fn solve(lines: Vec<String>, part: Part) -> u64 {
         );
     }
 
-    match part {
-        Part::One => {
-            let mut min_location = u64::MAX;
-            for seed in dataset.seeds {
-                let mut stage = "seed";
-                let mut value = seed;
-                while let Some(map) = dataset.maps.get(stage) {
-                    debug!("Stage {} -> {}", stage, map.target_domain);
-                    value = map.map(value);
-                    stage = &map.target_domain;
-                }
-                min_location = min_location.min(value);
-                info!("Final stage seed {} -> location {}", seed, value);
-            }
-            return min_location;
-        }
-        Part::Two => {
-            let mut min_location = u64::MAX;
-            for chunk in dataset.seeds.chunks_exact(2) {
-                info!("Computing range {} -> {}", chunk[0], chunk[0] + chunk[1]);
-                for seed in chunk[0]..(chunk[0] + chunk[1]) {
-                    let mut stage = "seed";
-                    let mut value = seed;
-                    while let Some(map) = dataset.maps.get(stage) {
-                        debug!("Stage {} -> {}", stage, map.target_domain);
-                        value = map.map(value);
-                        stage = &map.target_domain;
-                    }
-                    min_location = min_location.min(value);
-                    trace!("Final stage seed {} -> location {}", seed, value);
-                }
-            }
-            return min_location;
+    if let Part::Two = part {
+        // Convert the seeds to the new format !
+        let original_seeds = dataset.seeds;
+        let mut new_seeds : Vec<u64> = Vec::new();
+
+        for chunk in original_seeds.chunks_exact(2) {
+            let range = chunk[0]..(chunk[0]+chunk[1]);
+            // FIXME : don't do that it will eat all your memory: new_seeds.append(&mut range.collect::<Vec<u64>>());
         }
+        debug!("New seeds: {:?}", new_seeds);
+
+        dataset.seeds = new_seeds;
     }
+
+    let mut min_location = u64::MAX;
+    for seed in dataset.seeds {
+        let mut stage = "seed";
+        let mut value = seed;
+        while let Some(map) = dataset.maps.get(stage) {
+            debug!("Stage {} -> {}", stage, map.target_domain);
+            value = map.map(value);
+            stage = &map.target_domain;
+        }
+        min_location = min_location.min(value);
+        info!("Final stage seed {} -> location {}", seed, value);
+    }
+
+    min_location
 }
 
 #[cfg(test)]