Various Sushi

AtCoder
IDabc116_d
Time2000ms
Memory256MB
Difficulty
There are $N$ pieces of sushi. Each piece has two parameters: "kind of topping" $t_i$ and "deliciousness" $d_i$. You are choosing $K$ among these $N$ pieces to eat. Your "satisfaction" here will be calculated as follows: * The satisfaction is the sum of the "base total deliciousness" and the "variety bonus". * The base total deliciousness is the sum of the deliciousness of the pieces you eat. * The variety bonus is $x*x$, where $x$ is the number of different kinds of toppings of the pieces you eat. You want to have as much satisfaction as possible. Find this maximum satisfaction. ## Constraints * $1 \leq K \leq N \leq 10^5$ * $1 \leq t_i \leq N$ * $1 \leq d_i \leq 10^9$ * All values in input are integers. ## Input Input is given from Standard Input in the following format: $N$ $K$ $t_1$ $d_1$ $t_2$ $d_2$ $.$ $.$ $.$ $t_N$ $d_N$ [samples]
Samples
Input #1
5 3
1 9
1 7
2 6
2 5
3 1
Output #1
26

If you eat Sushi $1,2$ and $3$:

*   The base total deliciousness is $9+7+6=22$.
*   The variety bonus is $2*2=4$.

Thus, your satisfaction will be $26$, which is optimal.
Input #2
7 4
1 1
2 1
3 1
4 6
4 5
4 5
4 5
Output #2
25

It is optimal to eat Sushi $1,2,3$ and $4$.
Input #3
6 5
5 1000000000
2 990000000
3 980000000
6 970000000
6 960000000
4 950000000
Output #3
4900000016

Note that the output may not fit into a $32$\-bit integer type.
API Response (JSON)
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