From d30857a67e0f3278d9b57a284e1b6ee6f481a7a4 Mon Sep 17 00:00:00 2001 From: katarzynakaz Date: Sat, 18 Apr 2026 04:30:08 +0100 Subject: [PATCH 1/3] Add cache to fibonacci --- Sprint-2/improve_with_caches/fibonacci/fibonacci.py | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/Sprint-2/improve_with_caches/fibonacci/fibonacci.py b/Sprint-2/improve_with_caches/fibonacci/fibonacci.py index 60cc667..686115a 100644 --- a/Sprint-2/improve_with_caches/fibonacci/fibonacci.py +++ b/Sprint-2/improve_with_caches/fibonacci/fibonacci.py @@ -1,4 +1,12 @@ -def fibonacci(n): +def fibonacci(n, cache=None): + if cache is None: + cache = {} + + if n in cache: + return cache[n] + if n <= 1: return n - return fibonacci(n - 1) + fibonacci(n - 2) + + cache[n] = fibonacci(n - 1, cache) + fibonacci(n - 2, cache) + return cache[n] \ No newline at end of file From f43b0c08fa9afac6e7294ee389ae625bbb3b814c Mon Sep 17 00:00:00 2001 From: katarzynakaz Date: Sat, 18 Apr 2026 04:40:02 +0100 Subject: [PATCH 2/3] renamed --- .../improve_with_caches/fibonacci/fibonacci.py | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) diff --git a/Sprint-2/improve_with_caches/fibonacci/fibonacci.py b/Sprint-2/improve_with_caches/fibonacci/fibonacci.py index 686115a..6ee84d5 100644 --- a/Sprint-2/improve_with_caches/fibonacci/fibonacci.py +++ b/Sprint-2/improve_with_caches/fibonacci/fibonacci.py @@ -1,12 +1,12 @@ -def fibonacci(n, cache=None): - if cache is None: - cache = {} +def fibonacci(n, memo=None): + if memo is None: + memo = {} - if n in cache: - return cache[n] + if n in memo: + return memo[n] if n <= 1: return n - cache[n] = fibonacci(n - 1, cache) + fibonacci(n - 2, cache) - return cache[n] \ No newline at end of file + memo[n] = fibonacci(n - 1, memo) + fibonacci(n - 2, memo) + return memo[n] \ No newline at end of file From 3b2d83378c5f5ead9a744945b384f92ac67e8f7a Mon Sep 17 00:00:00 2001 From: katarzynakaz Date: Sat, 18 Apr 2026 05:00:18 +0100 Subject: [PATCH 3/3] add memoization to making_change --- .../making_change/making_change.py | 39 ++++++++++++------- 1 file changed, 24 insertions(+), 15 deletions(-) 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..1bac736 100644 --- a/Sprint-2/improve_with_caches/making_change/making_change.py +++ b/Sprint-2/improve_with_caches/making_change/making_change.py @@ -7,26 +7,35 @@ 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]) + coins = [200, 100, 50, 20, 10, 5, 2, 1] + memo = {} + return ways_to_make_change_helper(total, coins, 0, memo) - -def ways_to_make_change_helper(total: int, coins: List[int]) -> int: +def ways_to_make_change_helper(total: int, coins: List[int], coin_index: int, memo: dict) -> int: """ Helper function for ways_to_make_change to avoid exposing the coins parameter to callers. """ - if total == 0 or len(coins) == 0: + if total == 0: + return 1 + + if coin_index == len(coins): return 0 + + key = (total, coin_index) + + if key in memo: + return memo[key] + ways = 0 - for coin_index in range(len(coins)): - coin = coins[coin_index] - count_of_coin = 1 - while coin * count_of_coin <= total: - total_from_coins = coin * count_of_coin - if total_from_coins == total: - ways += 1 - else: - intermediate = ways_to_make_change_helper(total - total_from_coins, coins=coins[coin_index+1:]) - ways += intermediate - count_of_coin += 1 + coin = coins[coin_index] + count_of_coin = 0 + + while count_of_coin * coin <= total: + remaining = total - count_of_coin * coin + ways += ways_to_make_change_helper(remaining, coins, coin_index + 1, memo) + count_of_coin += 1 + + memo[key] = ways + return ways