code: def accuracy_lcs(self, label, pred):
          
          hit = 0.
          total = 0.
          batch_size = label.shape[0]
          for i in range(batch_size):
              l = self._remove_blank(label[i])
              p = []
              for k in range(self.seq_len):
                  p.append(np.argmax(pred[k * batch_size + i]))
              p = self.ctc_label(p)
              hit += self._lcs(p, l) * 1.0 / len(l)
              total += 1.0
          assert total == batch_size
          return hit / total
docs: Longest Common Subsequence accuracy measure: calculate accuracy of each prediction as LCS/length