Statement
There is a lemonade stand where customers can buy one lemonade at a time for $5 and pay with a $5, $10, or $20 bill. It is necessary to return the correct change to each customer so that the net transaction is completed successfully with a total payment of $5. Note that no change is available initially.
Given an integer array, bills
, where bills[i]
represents the bill paid by the ith customer, return TRUE if it is possible to provide every customer with the correct change, or FALSE otherwise.
Constraints:
1≤ bills.length
≤500
bills[i]
is either 5, 10, or 20.
Examples