diff --git a/datasets/SemanticKitti.py b/datasets/SemanticKitti.py
index 8eae642..ffd355f 100644
--- a/datasets/SemanticKitti.py
+++ b/datasets/SemanticKitti.py
@@ -772,9 +772,9 @@ class SemanticKittiSampler(Sampler):
                         if class_n < class_potentials.shape[0]:
                             _, class_indices = torch.topk(class_potentials, class_n, largest=False)
                         else:
-                            class_indices = torch.zeros((0,), dtype=torch.int32)
+                            class_indices = torch.zeros((0,), dtype=torch.int64)
                             while class_indices.shape[0] < class_n:
-                                new_class_inds = torch.randperm(class_potentials.shape[0]).type(torch.int32)
+                                new_class_inds = torch.randperm(class_potentials.shape[0]).type(torch.int64)
                                 class_indices = torch.cat((class_indices, new_class_inds), dim=0)
                             class_indices = class_indices[:class_n]
                         class_indices = self.dataset.class_frames[i][class_indices]