Recursion: Make Changes With Fewest Coins
Solution 1:
minCoins = change: minCoins is initialized with the value of change which is the maximum value that recMC can return as the minimum value of a coin is 1, assuming integer values of coins.
if change in coinValueList: return 1: base case 1 - if some coin has a value of that of change we just need to grab this 1 coin, thus returning 1
for i in [c for c in coinValueList if c <= change]::
The function then loops through all possible values of 1 single coin to
numCoins = 1 + recMC(coinValueList,change-i): deduct the coin value i from change, add 1 coin to the number of coins needed which is recursively calculated for the leftover change (change-i). This works inductively from the 2 base cases
if numCoins < minCoins: minCoins = numCoins inside this loop effectively assigns the smallest number of coins possible to minCoins
If change still had the initialized value of minCoins (implying no value c in coinValueList satisfies c <= change), this means that the number of coins needed is also the value of change, i.e. change 1-unit coins. This is base case 2 that is based on the pre-condition that the coin with value 1 is always available.
Post a Comment for "Recursion: Make Changes With Fewest Coins"