completed day 1 objectives

applications/expensive_seq/expensive_seq.py

@@ -1,8 +1,22 @@
 # Your code here
-
+cache = {}
 
 def expensive_seq(x, y, z):
     # Your code here
+    if (x, y, z) in cache:
+        return cache[(x, y, z)]
+
+    if x <= 0:
+        value = y + z
+    else:
+        value = expensive_seq(x - 1, y + 1, z) + expensive_seq(x - 2, y + 2, z * 2) + expensive_seq(x - 3, y + 3, z * 3)
+
+    cache[(x, y, z)] = value
+
+    return value
+
+
+print(cache)
 
 
 

hashtable/hashtable.py

@@ -22,6 +22,8 @@ class HashTable:
 
     def __init__(self, capacity):
         # Your code here
+        self.capacity = MIN_CAPACITY
+        self.table = [None] * capacity
 
 
     def get_num_slots(self):
@@ -35,6 +37,7 @@ def get_num_slots(self):
         Implement this.
         """
         # Your code here
+        return self.capacity
 
 
     def get_load_factor(self):
@@ -54,6 +57,15 @@ def fnv1(self, key):
         """
 
         # Your code here
+        fnv_prime = 2**40 + 2**8 + int('0xb3', 16)
+        hash = 14695981039346656037
+        key_bytes = key.encode()
+
+        for b in key_bytes:
+            hash = hash * fnv_prime
+            hash = hash ^ b
+
+        return hash
 
 
     def djb2(self, key):
@@ -63,6 +75,12 @@ def djb2(self, key):
         Implement this, and/or FNV-1.
         """
         # Your code here
+        hash = 5381
+
+        for char in key:
+            hash = 33 * hash ^ ord(char)
+
+        return hash
 
 
     def hash_index(self, key):
@@ -82,6 +100,9 @@ def put(self, key, value):
         Implement this.
         """
         # Your code here
+        i = self.hash_index(key)
+        self.table[i] = value
+
 
 
     def delete(self, key):
@@ -93,6 +114,12 @@ def delete(self, key):
         Implement this.
         """
         # Your code here
+        i = self.hash_index(key)
+
+        if self.table[i]:
+            self.table[i] = None
+        else:
+            print(f'{key} not found')
 
 
     def get(self, key):
@@ -104,6 +131,9 @@ def get(self, key):
         Implement this.
         """
         # Your code here
+        i = self.hash_index(key)
+
+        return self.table[i] if self.table[i] else None
 
 
     def resize(self, new_capacity):