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Author: Sonawane-Karan26

errata.md

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+# Errata, Corrections and Improvements
+----------------------------------------------------
+If you find any mistakes in the third edition of Hands On Data Structures and Algorithms with Python book, or if you have suggestions for improvements, then please [raise an issue in this repository]([https://github.com/PacktPublishing/JavaScript-from-Beginner-to-Professional/issues](https://github.com/PacktPublishing/Hands-On-Data-Structures-and-Algorithms-with-Python-Third-Edition/issues)), or email to us.
+
+## Chapter 13, Page 403 - Fixing the reference to `ord` array
+
+There should be a reference calling to the `ord` array as `ord_text` in the `generate_hash` function.
+
+Incorrect code is:
+```
+else:
+    hash_text[i] = ((hash_text[i-1] - ord_text[i-1]) + ord[i+len_pattern-1]) # calculating next hash value using previous value
+```
+Correct code is:
+```
+else:
+    hash_text[i] = ((hash_text[i-1] - ord_text[i-1]) + ord_text[i+len_pattern-1]) # calculating next hash value using previous value
+```