Hash Function
A hash function takes a data like string and outputs a hash, a fixed-size string or number.
E.g MD5 hash for a string “alok” is bad220c335d0c1f53548f6acdb17e265
import hashlib# initializing stringstr2hash = "alok"result = hashlib.md5(str2hash.encode())print(result.hexdigest())bad220c335d0c1f53548f6acdb17e265
Notes
- A given file will always have same hash but we can’t go back from hash to original value
- Sometime multiple string having same hash value, which is called hash collision.
Use cases of hash map
- Unordered map or dictionary : Creating a look up table in programming language.
- Preventing man-in-the-middle attack
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