8. Hashing

Hash Array:

pre-storing in a hash array/ freq array to reduce time complexity

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Character Hashing- 

1. without hashing-


  2.  with hashing-

     or
works only if 's' contains a to z                                     works for all characters: A to Z, a to z, others...

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NOTE-

1.   Stack overflow/ segmentation fault:-   MLE
      Runtime error-                                      index not available

2.   max size(int arr) : 10^6 (inside main),  10^7 (globally)

3.   a:97,  A:65,  total alphabets- 26

4. first priority to choose is unordered map, if TLE occurs then choose ordered map⭐

5. in a map, any data type can be a key (since it is implemented by red black tree) 
while it is not so in an unordered map (implemented by hash table)
-------------------------------------------------------------------------------------------------------------                                                            COLLISIONS-(u may ignore)

collision is when similar wale goes to same hash place.



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