Say we have n=10
then 10 is only divisible by 2, so 10 can be exchanged for 5 2 rupees coins or 10/3=3 or 3 rupees coin also
can provide some other test cases also
Question is not clear
yes also consider 10/3=3 also
A coin n can be exchanged in a bank into three coins: n/2, n/3 and n/4
for 12 you go to bank exchange it into 6 4 3
now you can get 6+4+3=13 gram of gold
So 13 is ans
i hope this helps
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