fix list concat bug

PaddleRec/tdm/tdm_demo/train_network.py

@@ -144,10 +144,12 @@ class TdmTrainNet(object):
                   self.need_trace, self.need_detail)
 
         tdm_fc_re = fluid.layers.reshape(tdm_fc, [-1, 2])
+        sample_label = fluid.layers.concat(sample_label, axis=1)
         labels_reshape = fluid.layers.reshape(sample_label, [-1, 1])
         cost, softmax_prob = fluid.layers.softmax_with_cross_entropy(
             logits=tdm_fc_re, label=labels_reshape, return_softmax=True)
 
+        sample_mask = fluid.layers.concat(sample_mask, axis=1)
         mask_reshape = fluid.layers.reshape(sample_mask, [-1, 1])
         mask_index = fluid.layers.where(mask_reshape != 0)
         mask_cost = fluid.layers.gather_nd(cost, mask_index)