COINS - Bytelandian gold coins

In Byteland they have a very strange monetary system.

Each Bytelandian gold coin has an integer number written on it. A coin n can be exchanged in a bank into three coins: n/2, n/3 and n/4. But these numbers are all rounded down (the banks have to make a profit).

You can also sell Bytelandian coins for American dollars. The exchange rate is 1:1. But you can not buy Bytelandian coins.

You have one gold coin. What is the maximum amount of American dollars you can get for it?


The input will contain several test cases (not more than 10). Each testcase is a single line with a number n, 0 <= n <= 1 000 000 000. It is the number written on your coin.


For each test case output a single line, containing the maximum amount of American dollars you can make.




You can change 12 into 6, 4 and 3, and then change these into $6+$4+$3 = $13. If you try changing the coin 2 into 3 smaller coins, you will get 1, 0 and 0, and later you can get no more than $1 out of them. It is better just to change the 2 coin directly into $2.

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abualy: 2018-03-13 11:17:06

recursion, and memory array, solved with GO

badasshackme: 2018-03-10 19:26:23

@pavanjupalli precompute some cases, see

pavanjupalli: 2018-03-02 16:39:14

it shows time limit exceeded problem , can anyone here help me

shivam_mnnit: 2018-03-01 20:50:49

No need to use map,using simple recursion would give better pre compute the results upto 10^6 and then use recursion to compute further results.

sanjitpd_777: 2018-03-01 16:21:03

recursion and map ;
that's it :)

surajgoel1225: 2018-02-26 06:49:29

ac in third go :) :)

knodelmj: 2018-02-18 16:08:41

nice problem!
for c# programmers (if any here): using dictionaries will help, I couldn't get AC with arrays... however with dictionary and memorization I have AC in 0.00

rdrsadhu: 2018-01-20 10:15:37

For Python use

for line in sys.stdin:

hari_krishna_6: 2018-01-11 12:39:42

no need of dp just use recursion . AC in one Go.!!

as3eem: 2018-01-06 04:27:03

I wouldn't have commented this if I hadn't suffered. Seriously @viniet_sw .... +1 for your comment.
motherfucker long long int

Last edit: 2018-01-06 04:39:46

Added by:Tomek Czajka
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Memory limit:1536MB
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