Problem A
Evening Fika
Languages
en
sv
Sara loves fika! She has just received $P$ Swedish kronor from her mom to buy some evening fika. Since Sara is smart, she will try to spend the money as wisely as possible. At the store Lugnbyrån, there are $N$ pastries available. Each pastry has a certain price and a specific category. Because Sara likes fika so much, she almost thinks all kinds of pastries are equally tasty. Namely, she has no preference for which category of pastry to buy, but she feels it would be a bit too monotonous if she buys more than $K$ pastries of the same category.
Help Sara buy as many pastries as possible, with a total cost less than or equal to $P$. Also, ensure that there are no more than $K$ pastries from the same category among those she bought. You only need to print out how many pastries she can buy, not which ones.
Input
The first line of the input contains the integer $N$ ($1 \leq N \leq 10^5$), the number of pastries Sara can choose from.
The next line contains the integer $P$ ($1 \leq P \leq 10^8$), the number of kronor Sara has as a budget for her evening fika.
The next line contains the integer $K$ ($1 \leq K \leq N$), the maximum number of pastries from each category that Sara is willing to eat.
The next line contains the integers $c_1, c_2, \dots , c_N$ ($1 \leq c_i \leq P$), where $c_i$ means that that pastry $i$ costs $c_i$ kronor. Note that the total cost of all pastries may not necessarily fit in a 32-bit integer.
The last line contains the integers $t_1, t_2, \dots , t_N$ ($1 \leq t_i \leq 10^5$). There are exactly $10^5$ categories of pastries, and we refer to each with an integer. Each $t_i$ means that that pastry $i$ belongs to category $t_i$.
Output
Print an integer: the number of pastries that Sara can buy if she uses her budget optimally.
Points
Your solution will be tested on several test case groups. To get the points for a group, it must pass all the test cases in the group.
Group |
Point value |
Constraints |
$1$ |
$20$ |
The subtask has a single testcase, the one on the poster (https://www.progolymp.se/2025/affisch.pdf). |
$2$ |
$5$ |
$K=N$ and you can afford to buy every single pastry. |
$3$ |
$15$ |
You can afford to buy every single pastry. |
$4$ |
$5$ |
$c_i=1$, that is to say every pastry costs $1$ krona. |
$5$ |
$17$ |
$K=N, N \leq 500$ |
$6$ |
$21$ |
$K=N$ |
$7$ |
$9$ |
$N \leq 500$ |
$8$ |
$8$ |
No additional constraints. |
Explanation of Sample 1
In this sample, Sara can afford to buy all the pastries, but they all belong to the same category (category 1). Since she can buy at most 2 per category, she can purchase 2 of them.
Explanation of Sample 2
In this sample, categories are not a problem because $K$ is large, but Sara cannot afford to buy all the pastries. If she buys the pastries priced at $4, 3, 2, 1$, she can afford exactly 4.
Explanation of Sample 3
An optimal solution is to buy pastries priced at $1, 1, 4, 5$. Here, Sara could have bought more pastries if not limited by the categories.
Sample Input 1 | Sample Output 1 |
---|---|
3 10 2 2 3 2 1 1 1 |
2 |
Sample Input 2 | Sample Output 2 |
---|---|
5 10 5 4 3 2 5 1 1 1 1 1 1 |
4 |
Sample Input 3 | Sample Output 3 |
---|---|
9 13 2 5 1 7 8 5 7 1 4 1 1 2 1 1 3 3 2 1 2 |
4 |