1 files changed, 28 insertions(+), 11 deletions(-)

M codes/tsp_hw01/src/tsp.rs

@@ 266,12 266,18 @@ where
 }
 
 pub struct ReverseSubsequencePerturbation<D> {
-    _phantom: PhantomData<D>
+    _phantom: PhantomData<D>,
+    min_subsequence_len: usize,
+    max_subsequence_len: usize,
 }
 
 impl<D> ReverseSubsequencePerturbation<D> {
     pub fn new() -> Self {
-        Self { _phantom: PhantomData }
+        Self {
+            _phantom: PhantomData,
+            max_subsequence_len: usize::MAX,
+            min_subsequence_len: 0,
+        }
     }
 }
 


@@ 284,20 290,31 @@ where
     type Chromosome = NodePermutation<D>;
 
     fn perturb(&self, chromosome: &mut Self::Chromosome, rng: &mut dyn RngCore) {
-        let first = rng.random_range(0..chromosome.permutation.len());
-        let second = rng.random_range(0..chromosome.permutation.len());
-
-        let start = first.min(second);
-        let end = first.max(second);
+        let len = chromosome.permutation.len();
+        let index = rng.random_range(0..chromosome.permutation.len());
+        let subsequence_len = rng.random_range(
+            self.min_subsequence_len..(chromosome.permutation.len().min(self.max_subsequence_len))
+        );
 
         // Reverse the subsequence between start and end (inclusive)
-        let mut left = start;
-        let mut right = end;
+        let mut left = index;
+        let mut right = (index + subsequence_len) % len;
 
-        while left < right {
+        while left != right {
             chromosome.permutation.swap_rows(left, right);
+
             left += 1;
-            right -= 1;
+            left %= len;
+
+            if left == right {
+                break;
+            }
+
+            if right > 0 {
+                right -= 1;
+            } else {
+                right = len - 1;
+            }
         }
     }
 }