Delhi Metro Smart Card Balance Validator
Delhi Metro Smart Card Balance Validator
MediumArrays100% accepted
Priya uses Delhi Metro Smart Card with minimum balance requirement of ₹10. Given initial balance and transaction array (negative=debit, positive=recharge), find first transaction violating the minimum balance requirement.
Approach
Given initial balance and array of transactions, return index of first transaction bringing balance below ₹10, or -1 if valid throughout.
Input
initial=50,transactions=[-35,-10,-8]
Output
1
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