2073_time_needed_to_buy_tickets.py

"""
2073. Time Needed to Buy Tickets

There are n people in a line queuing to buy tickets,
 where the 0th person is at the front of the line and 
 the (n - 1)th person is at the back of the line.

You are given a 0-indexed integer array tickets of length
n where the number of tickets that the ith person would 
like to buy is tickets[i].

Each person takes exactly 1 second to buy a ticket. A person 
can only buy 1 ticket at a time and has to go back to the end 
of the line (which happens instantaneously) in order to buy 
more tickets. If a person does not have any tickets left to 
buy, the person will leave the line.

Return the time taken for the person at position k (0-indexed) 
to finish buying tickets.
"""

class Solution(object):
    def timeRequiredToBuy(self, tickets, k):
        """
        :type tickets: List[int]
        :type k: int
        :rtype: int
        """
        time = 0
        for i in range(len(tickets)):
            if i <= k:
                time += min(tickets[i], tickets[k])
            else:
                time += min(tickets[i], tickets[k] - 1)

        return time

s = Solution()

# Case 1
output = s.timeRequiredToBuy(tickets=[2,3,2], k=2)
expected = 6
print(f"Result: {output}, Expected: {expected}")
assert output == expected

# Case 2
output = s.timeRequiredToBuy(tickets=[5,1,1,1], k=0)
expected = 8
print(f"Result: {output}, Expected: {expected}")
assert output == expected