diff --git a/Sprint-2/improve_with_caches/fibonacci/fibonacci.py b/Sprint-2/improve_with_caches/fibonacci/fibonacci.py index 60cc667..849d68e 100644 --- a/Sprint-2/improve_with_caches/fibonacci/fibonacci.py +++ b/Sprint-2/improve_with_caches/fibonacci/fibonacci.py @@ -1,4 +1,17 @@ +# Cache dictionary to store computed Fibonacci values +fib_cache = {} + def fibonacci(n): + # Check if we already computed this value + if n in fib_cache: + return fib_cache[n] + + # Base cases if n <= 1: + fib_cache[n] = n return n - return fibonacci(n - 1) + fibonacci(n - 2) + + # Recursive case with caching + result = fibonacci(n - 1) + fibonacci(n - 2) + fib_cache[n] = result + return result \ No newline at end of file diff --git a/Sprint-2/improve_with_caches/making_change/making_change.py b/Sprint-2/improve_with_caches/making_change/making_change.py index 255612e..61cd4d3 100644 --- a/Sprint-2/improve_with_caches/making_change/making_change.py +++ b/Sprint-2/improve_with_caches/making_change/making_change.py @@ -1,5 +1,8 @@ from typing import List +# Cache dictionary to store computed results +# Key: (total, tuple(coins)) -> Value: number of ways +change_cache = {} def ways_to_make_change(total: int) -> int: """ @@ -7,15 +10,28 @@ def ways_to_make_change(total: int) -> int: For instance, there are two ways to make a value of 3: with 3x 1 coins, or with 1x 1 coin and 1x 2 coin. """ - return ways_to_make_change_helper(total, [200, 100, 50, 20, 10, 5, 2, 1]) + # Clear cache for each new call to avoid interference between tests + change_cache.clear() + coins = [200, 100, 50, 20, 10, 5, 2, 1] + return ways_to_make_change_helper(total, coins) def ways_to_make_change_helper(total: int, coins: List[int]) -> int: """ Helper function for ways_to_make_change to avoid exposing the coins parameter to callers. """ - if total == 0 or len(coins) == 0: - return 0 + # Create a cache key - use tuple of coins since lists are not hashable + cache_key = (total, tuple(coins)) + + # Check if we already computed this combination + if cache_key in change_cache: + return change_cache[cache_key] + + # Base cases + if total == 0: + return 1 # One way to make 0: use no coins + if len(coins) == 0: + return 0 # No coins left but still need to make total > 0 ways = 0 for coin_index in range(len(coins)): @@ -29,4 +45,7 @@ def ways_to_make_change_helper(total: int, coins: List[int]) -> int: intermediate = ways_to_make_change_helper(total - total_from_coins, coins=coins[coin_index+1:]) ways += intermediate count_of_coin += 1 - return ways + + # Store result in cache before returning + change_cache[cache_key] = ways + return ways \ No newline at end of file