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diff --git a/src/day09.rs b/src/day09.rs
index 8ad49bb..eac0b8c 100644 (file)
--- a/src/day09.rs
+++ b/src/day09.rs
@@ -69,7 +69,7 @@ pub fn defrag_v2(mut memory: Vec<u32>) -> Vec<u32> {
     let mut files: Vec<MemoryChunk> = Vec::new();
 
     let mut pos = 0;
-    loop {
+    while pos < memory.len() {
         let start = pos;
         let v = memory[start];
         pos += 1;
@@ -87,14 +87,11 @@ pub fn defrag_v2(mut memory: Vec<u32>) -> Vec<u32> {
         } else {
             files.push(chunk);
         }
-
-        if pos == memory.len() {
-            break;
-        }
     }
 
     for f in files.iter().rev() {
         for free_space in free_spaces.iter_mut() {
+            // Files are only move backward.
             if free_space.pos >= f.pos {
                 break;
             }