You cannot submit for this problem because the contest is ended. You can click "Open in Problem Set" to view this problem in normal mode.

Description

Input

The first line of the input contains two integers $n$ and $k$ ($1 \le k \le n \le 2 \cdot 10^5$) — the number of hits and the maximum number of times you can push the same button in a row.

The second line of the input contains $n$ integers $a_1, a_2, \dots, a_n$ ($1 \le a_i \le 10^9$), where $a_i$ is the damage of the $i$-th hit.

The third line of the input contains the string $s$ consisting of exactly $n$ lowercase Latin letters — the sequence of hits (each character is the letter on the button you need to press to perform the corresponding hit).

Output

Print one integer $dmg$ — the maximum possible damage to the opponent's character you can deal without breaking your gamepad buttons.

7 3
1 5 16 18 7 2 10
baaaaca

54

5 5
2 4 1 3 1000
aaaaa

1010

5 4
2 4 1 3 1000
aaaaa

1009

8 1
10 15 2 1 4 8 15 16
qqwweerr

41

6 3
14 18 9 19 2 15
cccccc

52

2 1
10 10
qq

10

Note

In the first example you can choose hits with numbers $[1, 3, 4, 5, 6, 7]$ with the total damage $1 + 16 + 18 + 7 + 2 + 10 = 54$.

In the second example you can choose all hits so the total damage is $2 + 4 + 1 + 3 + 1000 = 1010$.

In the third example you can choose all hits expect the third one so the total damage is $2 + 4 + 3 + 1000 = 1009$.

In the fourth example you can choose hits with numbers $[2, 3, 6, 8]$. Only this way you can reach the maximum total damage $15 + 2 + 8 + 16 = 41$.

In the fifth example you can choose only hits with numbers $[2, 4, 6]$ with the total damage $18 + 19 + 15 = 52$.

In the sixth example you can change either first hit or the second hit (it does not matter) with the total damage $10$.