Added delete function in separate copy of code

computing_sh/Python11_Hash_Table_Search.ipynb

@@ -207,4 +207,100 @@
       ]
     }
   ]
-}
+}
+
+
+# hash function
+def hash(key):
+  return key % N 
+
+def insert(key, data):
+  index = hash(key)
+  if hash_table[index] == -1: # available
+    hash_table[index] = data
+  else: # collision
+    i = index + 1
+    while hash_table[i] != -1:
+      i += 1
+    hash_table[i] = data 
+
+def search(key, data):
+  index = hash(key)
+  if hash_table[index] == data: # found
+    return "BINGO!"
+  elif hash_table[index] == -1:
+    return "Not found"
+  else: # collided records
+    i = index + 1
+    if i<len(hash_table):
+        while hash_table[i] != -1:
+          if hash_table[i] == data: # found in collided records
+            return "FINALLY!"
+          else:
+            i += 1
+    return "Unfortunately" 
+
+def delete(key, data):
+  if search(key, data) == "BINGO!": # foudn in uncollided records
+    index = hash(key) # find the index
+    hash_table[index] = -1
+    return "Deleted (Non-Collision)"
+  elif search(key, data) == "FINALLY!": # collided records
+    index = hash(key) # find the index
+    i = (index + 1) % N
+    while hash_table[i] != -1:
+      if hash_table[i] == data:
+        hash_table[i] = -1
+        return "Deleted (Collision)"
+  else:
+    return "Not Deleted (Not found)"
+
+# insert
+records = {991: "Tom", 992: "Mary", 993: "Ali"} # insert without collision
+for key, value in records.items(): #.items() function needed because records is in a dictionary
+  insert(key, value)
+insert(1003, "Peter") # insert with collision
+print(hash_table)
+
+# main
+N = 10
+hash_table = [-1 for i in range(N)]
+print(hash_table)
+
+records = {1234: "Tom", 321: "Mary", 659: "Ali"}
+print(records)
+
+# insert without collision
+for key, value in records.items():
+  insert(key, value)
+print(hash_table)
+
+# insert with collision
+insert(784, "Peter")
+print(hash_table)
+
+# search without collision
+print(search(659, "Ali")) # successful
+print(search(882, "Lucy")) # unsuccessful
+
+# search with collision
+print(search(784, "Peter")) # successful
+print(search(404, "John")) # unsuccessful
+
+# update without collision
+print(update(659, "Ali", "Ali2")) # successful
+print(update(321, "Ahmad", "Ahmad2")) # unsuccessful
+
+# update with collision
+print(update(784, "Peter", "Peter2")) # successful
+print(update(784, "Roy", "Roy2")) # unsuccessful
+
+# delete without collision
+print(delete(321, "Mary"))
+
+# delete with collision
+print(delete(784, "Peter2"))
+
+# unsuccessful deleted (with and without collision)
+print(delete(999, "Bala"))
+print(hash_table)