diff --git a/egs/librispeech/ASR/pruned_transducer_stateless2/beam_search.py b/egs/librispeech/ASR/pruned_transducer_stateless2/beam_search.py
index fd59d4b7f..abb5fe4ff 100644
--- a/egs/librispeech/ASR/pruned_transducer_stateless2/beam_search.py
+++ b/egs/librispeech/ASR/pruned_transducer_stateless2/beam_search.py
@@ -719,7 +719,7 @@ def greedy_search_batch(
     encoder_out = model.joiner.encoder_proj(packed_encoder_out.data)
 
     offset = 0
-    for (t, batch_size) in enumerate(batch_size_list):
+    for t, batch_size in enumerate(batch_size_list):
         start = offset
         end = offset + batch_size
         current_encoder_out = encoder_out.data[start:end]
@@ -779,6 +779,74 @@ def greedy_search_batch(
         )
 
 
+def deprecated_greedy_search_batch(
+    model: nn.Module, encoder_out: torch.Tensor
+) -> List[List[int]]:
+    """Greedy search in batch mode. It hardcodes --max-sym-per-frame=1.
+    Args:
+      model:
+        The transducer model.
+      encoder_out:
+        Output from the encoder. Its shape is (N, T, C), where N >= 1.
+    Returns:
+      Return a list-of-list of token IDs containing the decoded results.
+      len(ans) equals to encoder_out.size(0).
+    """
+    assert encoder_out.ndim == 3
+    assert encoder_out.size(0) >= 1, encoder_out.size(0)
+
+    device = next(model.parameters()).device
+
+    batch_size = encoder_out.size(0)
+    T = encoder_out.size(1)
+
+    blank_id = model.decoder.blank_id
+    unk_id = getattr(model, "unk_id", blank_id)
+    context_size = model.decoder.context_size
+
+    hyps = [[blank_id] * context_size for _ in range(batch_size)]
+
+    decoder_input = torch.tensor(
+        hyps,
+        device=device,
+        dtype=torch.int64,
+    )  # (batch_size, context_size)
+
+    decoder_out = model.decoder(decoder_input, need_pad=False)
+    decoder_out = model.joiner.decoder_proj(decoder_out)
+    encoder_out = model.joiner.encoder_proj(encoder_out)
+
+    # decoder_out: (batch_size, 1, decoder_out_dim)
+    for t in range(T):
+        current_encoder_out = encoder_out[:, t : t + 1, :].unsqueeze(2)  # noqa
+        # current_encoder_out's shape: (batch_size, 1, 1, encoder_out_dim)
+        logits = model.joiner(
+            current_encoder_out, decoder_out.unsqueeze(1), project_input=False
+        )
+        # logits'shape (batch_size, 1, 1, vocab_size)
+        logits = logits.squeeze(1).squeeze(1)  # (batch_size, vocab_size)
+        assert logits.ndim == 2, logits.shape
+        y = logits.argmax(dim=1).tolist()
+        emitted = False
+        for i, v in enumerate(y):
+            if v not in (blank_id, unk_id):
+                hyps[i].append(v)
+                emitted = True
+        if emitted:
+            # update decoder output
+            decoder_input = [h[-context_size:] for h in hyps]
+            decoder_input = torch.tensor(
+                decoder_input,
+                device=device,
+                dtype=torch.int64,
+            )
+            decoder_out = model.decoder(decoder_input, need_pad=False)
+            decoder_out = model.joiner.decoder_proj(decoder_out)
+
+    ans = [h[context_size:] for h in hyps]
+    return ans
+
+
 @dataclass
 class Hypothesis:
     # The predicted tokens so far.
@@ -1019,7 +1087,7 @@ def modified_beam_search(
 
     offset = 0
     finalized_B = []
-    for (t, batch_size) in enumerate(batch_size_list):
+    for t, batch_size in enumerate(batch_size_list):
         start = offset
         end = offset + batch_size
         current_encoder_out = encoder_out.data[start:end]
@@ -1227,7 +1295,7 @@ def modified_beam_search_lm_rescore(
 
     offset = 0
     finalized_B = []
-    for (t, batch_size) in enumerate(batch_size_list):
+    for t, batch_size in enumerate(batch_size_list):
         start = offset
         end = offset + batch_size
         current_encoder_out = encoder_out.data[start:end]
@@ -1427,7 +1495,7 @@ def modified_beam_search_lm_rescore_LODR(
 
     offset = 0
     finalized_B = []
-    for (t, batch_size) in enumerate(batch_size_list):
+    for t, batch_size in enumerate(batch_size_list):
         start = offset
         end = offset + batch_size
         current_encoder_out = encoder_out.data[start:end]
@@ -2599,7 +2667,6 @@ def modified_beam_search_LODR(
                 hyp_log_prob = topk_log_probs[k]  # get score of current hyp
                 new_token = topk_token_indexes[k]
                 if new_token not in (blank_id, unk_id):
-
                     ys.append(new_token)
                     state_cost = hyp.state_cost.forward_one_step(new_token)
 
@@ -2721,7 +2788,7 @@ def modified_beam_search_lm_shallow_fusion(
 
     offset = 0
     finalized_B = []
-    for (t, batch_size) in enumerate(batch_size_list):
+    for t, batch_size in enumerate(batch_size_list):
         start = offset
         end = offset + batch_size
         current_encoder_out = encoder_out.data[start:end]  # get batch
@@ -2863,7 +2930,6 @@ def modified_beam_search_lm_shallow_fusion(
                 new_token = topk_token_indexes[k]
                 new_timestamp = hyp.timestamp[:]
                 if new_token not in (blank_id, unk_id):
-
                     ys.append(new_token)
                     new_timestamp.append(t)
 
diff --git a/egs/librispeech/ASR/zipformer/decode.py b/egs/librispeech/ASR/zipformer/decode.py
index 93680602e..41d54ea50 100755
--- a/egs/librispeech/ASR/zipformer/decode.py
+++ b/egs/librispeech/ASR/zipformer/decode.py
@@ -108,6 +108,7 @@ import torch.nn as nn
 from asr_datamodule import LibriSpeechAsrDataModule
 from beam_search import (
     beam_search,
+    deprecated_greedy_search_batch,
     fast_beam_search_nbest,
     fast_beam_search_nbest_LG,
     fast_beam_search_nbest_oracle,
@@ -116,7 +117,7 @@ from beam_search import (
     greedy_search_batch,
     modified_beam_search,
 )
-from train import add_model_arguments, get_params, get_model
+from train import add_model_arguments, get_model, get_params
 
 from icefall.checkpoint import (
     average_checkpoints,
@@ -273,8 +274,7 @@ def get_parser():
         "--context-size",
         type=int,
         default=2,
-        help="The context size in the decoder. 1 means bigram; "
-        "2 means tri-gram",
+        help="The context size in the decoder. 1 means bigram; " "2 means tri-gram",
     )
     parser.add_argument(
         "--max-sym-per-frame",
@@ -425,14 +425,15 @@ def decode_one_batch(
         )
         for hyp in sp.decode(hyp_tokens):
             hyps.append(hyp.split())
-    elif (
-        params.decoding_method == "greedy_search"
-        and params.max_sym_per_frame == 1
-    ):
-        hyp_tokens = greedy_search_batch(
+    elif params.decoding_method == "greedy_search" and params.max_sym_per_frame == 1:
+        # hyp_tokens = greedy_search_batch(
+        #     model=model,
+        #     encoder_out=encoder_out,
+        #     encoder_out_lens=encoder_out_lens,
+        # )
+        hyp_tokens = deprecated_greedy_search_batch(
             model=model,
             encoder_out=encoder_out,
-            encoder_out_lens=encoder_out_lens,
         )
         for hyp in sp.decode(hyp_tokens):
             hyps.append(hyp.split())
@@ -559,9 +560,7 @@ def decode_dataset(
         if batch_idx % log_interval == 0:
             batch_str = f"{batch_idx}/{num_batches}"
 
-            logging.info(
-                f"batch {batch_str}, cuts processed until now is {num_cuts}"
-            )
+            logging.info(f"batch {batch_str}, cuts processed until now is {num_cuts}")
     return results
 
 
@@ -594,8 +593,7 @@ def save_results(
 
     test_set_wers = sorted(test_set_wers.items(), key=lambda x: x[1])
     errs_info = (
-        params.res_dir
-        / f"wer-summary-{test_set_name}-{key}-{params.suffix}.txt"
+        params.res_dir / f"wer-summary-{test_set_name}-{key}-{params.suffix}.txt"
     )
     with open(errs_info, "w") as f:
         print("settings\tWER", file=f)
@@ -656,9 +654,7 @@ def main():
             if "LG" in params.decoding_method:
                 params.suffix += f"-ngram-lm-scale-{params.ngram_lm_scale}"
     elif "beam_search" in params.decoding_method:
-        params.suffix += (
-            f"-{params.decoding_method}-beam-size-{params.beam_size}"
-        )
+        params.suffix += f"-{params.decoding_method}-beam-size-{params.beam_size}"
     else:
         params.suffix += f"-context-{params.context_size}"
         params.suffix += f"-max-sym-per-frame-{params.max_sym_per_frame}"
@@ -690,9 +686,9 @@ def main():
 
     if not params.use_averaged_model:
         if params.iter > 0:
-            filenames = find_checkpoints(
-                params.exp_dir, iteration=-params.iter
-            )[: params.avg]
+            filenames = find_checkpoints(params.exp_dir, iteration=-params.iter)[
+                : params.avg
+            ]
             if len(filenames) == 0:
                 raise ValueError(
                     f"No checkpoints found for"
@@ -719,9 +715,9 @@ def main():
             model.load_state_dict(average_checkpoints(filenames, device=device))
     else:
         if params.iter > 0:
-            filenames = find_checkpoints(
-                params.exp_dir, iteration=-params.iter
-            )[: params.avg + 1]
+            filenames = find_checkpoints(params.exp_dir, iteration=-params.iter)[
+                : params.avg + 1
+            ]
             if len(filenames) == 0:
                 raise ValueError(
                     f"No checkpoints found for"
@@ -780,9 +776,7 @@ def main():
             decoding_graph.scores *= params.ngram_lm_scale
         else:
             word_table = None
-            decoding_graph = k2.trivial_graph(
-                params.vocab_size - 1, device=device
-            )
+            decoding_graph = k2.trivial_graph(params.vocab_size - 1, device=device)
     else:
         decoding_graph = None
         word_table = None