From 5b66a24b4ad535778fa407aec56b41659f688e89 Mon Sep 17 00:00:00 2001 From: pawareliza14 <135448125+pawareliza14@users.noreply.github.com> Date: Tue, 7 Oct 2025 01:00:05 +0530 Subject: [PATCH 1/2] Create inverse_coin_change.py --- backtracking/inverse_coin_change.py | 47 +++++++++++++++++++++++++++++ 1 file changed, 47 insertions(+) create mode 100644 backtracking/inverse_coin_change.py diff --git a/backtracking/inverse_coin_change.py b/backtracking/inverse_coin_change.py new file mode 100644 index 000000000000..440804026a02 --- /dev/null +++ b/backtracking/inverse_coin_change.py @@ -0,0 +1,47 @@ +def inverse_coin_change(amount, coins): + """ + Finds all combinations of coins that sum up to the given amount. + + :param amount: Target amount + :param coins: List of coin denominations + :return: List of combinations (each combination is a list of coins) + """ + results = [] + + def backtrack(remaining, combo, start): + if remaining == 0: + results.append(list(combo)) + return + for i in range(start, len(coins)): + coin = coins[i] + if coin <= remaining: + combo.append(coin) + backtrack(remaining - coin, combo, i) # allow reuse + combo.pop() + + coins.sort() + backtrack(amount, [], 0) + return results + + +def main(): + import argparse + + parser = argparse.ArgumentParser(description="Inverse Coin Change Solver") + parser.add_argument("--amount", type=int, required=True, help="Target amount to reach") + parser.add_argument("--coins", type=int, nargs="+", required=True, help="List of coin denominations") + + args = parser.parse_args() + + solutions = inverse_coin_change(args.amount, args.coins) + + if not solutions: + print(f"No combinations found to make {args.amount} using coins {args.coins}") + else: + print(f"Combinations to make {args.amount} using coins {args.coins}:") + for combo in solutions: + print(combo) + + +if __name__ == "__main__": + main() From 41bb691c7c46400f433ac67d93be09e427861f85 Mon Sep 17 00:00:00 2001 From: "pre-commit-ci[bot]" <66853113+pre-commit-ci[bot]@users.noreply.github.com> Date: Mon, 6 Oct 2025 19:41:17 +0000 Subject: [PATCH 2/2] [pre-commit.ci] auto fixes from pre-commit.com hooks for more information, see https://pre-commit.ci --- backtracking/inverse_coin_change.py | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/backtracking/inverse_coin_change.py b/backtracking/inverse_coin_change.py index 440804026a02..f5c30ebcec64 100644 --- a/backtracking/inverse_coin_change.py +++ b/backtracking/inverse_coin_change.py @@ -1,7 +1,7 @@ def inverse_coin_change(amount, coins): """ Finds all combinations of coins that sum up to the given amount. - + :param amount: Target amount :param coins: List of coin denominations :return: List of combinations (each combination is a list of coins) @@ -28,8 +28,12 @@ def main(): import argparse parser = argparse.ArgumentParser(description="Inverse Coin Change Solver") - parser.add_argument("--amount", type=int, required=True, help="Target amount to reach") - parser.add_argument("--coins", type=int, nargs="+", required=True, help="List of coin denominations") + parser.add_argument( + "--amount", type=int, required=True, help="Target amount to reach" + ) + parser.add_argument( + "--coins", type=int, nargs="+", required=True, help="List of coin denominations" + ) args = parser.parse_args()