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* Add the intial translation of code of all the languages * test * revert * Remove * Add Python and Java code for EN version
48 lines
1.6 KiB
Python
48 lines
1.6 KiB
Python
"""
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File: coin_change_greedy.py
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Created Time: 2023-07-18
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Author: krahets (krahets@163.com)
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"""
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def coin_change_greedy(coins: list[int], amt: int) -> int:
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"""Coin change: Greedy"""
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# Assume coins list is ordered
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i = len(coins) - 1
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count = 0
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# Loop for greedy selection until no remaining amount
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while amt > 0:
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# Find the smallest coin close to and less than the remaining amount
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while i > 0 and coins[i] > amt:
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i -= 1
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# Choose coins[i]
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amt -= coins[i]
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count += 1
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# If no feasible solution is found, return -1
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return count if amt == 0 else -1
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"""Driver Code"""
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if __name__ == "__main__":
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# Greedy: can ensure finding a global optimal solution
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coins = [1, 5, 10, 20, 50, 100]
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amt = 186
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res = coin_change_greedy(coins, amt)
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print(f"\ncoins = {coins}, amt = {amt}")
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print(f"The minimum number of coins needed to make up {amt} is {res}")
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# Greedy: cannot ensure finding a global optimal solution
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coins = [1, 20, 50]
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amt = 60
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res = coin_change_greedy(coins, amt)
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print(f"\ncoins = {coins}, amt = {amt}")
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print(f"The minimum number of coins needed to make up {amt} is {res}")
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print(f"In reality, the minimum number needed is 3, i.e., 20 + 20 + 20")
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# Greedy: cannot ensure finding a global optimal solution
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coins = [1, 49, 50]
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amt = 98
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res = coin_change_greedy(coins, amt)
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print(f"\ncoins = {coins}, amt = {amt}")
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print(f"The minimum number of coins needed to make up {amt} is {res}")
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print(f"In reality, the minimum number needed is 2, i.e., 49 + 49")
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