You are playing a new famous fighting game: Kortal Mombat XII. You have to perform a brutality on your opponent's character.

You are playing the game on the new generation console so your gamepad have 26 buttons. Each button has a single lowercase Latin letter from 'a' to 'z' written on it. All the letters on buttons are pairwise distinct.

You are given a sequence of hits, the i-th hit deals a_i units of damage to the opponent's character. To perform the i-th hit you have to press the button s_i on your gamepad. Hits are numbered from 1 to n.

You know that if you press some button more than k times in a row then it'll break. You cherish your gamepad and don't want to break any of its buttons.

To perform a brutality you have to land some of the hits of the given sequence. You are allowed to skip any of them, however changing the initial order of the sequence is prohibited. The total damage dealt is the sum of a_i over all i for the hits which weren't skipped.

Note that if you skip the hit then the counter of consecutive presses the button won't reset.

Your task is to skip some hits to deal the maximum possible total damage to the opponent's character and not break your gamepad buttons.

Input

The first line of the input contains two integers n and k (1 ≤ k ≤ n ≤ 2 ⋅ 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, ..., a_n (1 ≤ a_i ≤ 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.

Examples

Input


7 3
1 5 16 18 7 2 10
baaaaca


Output


54


Input


5 5
2 4 1 3 1000
aaaaa


Output


1010


Input


5 4
2 4 1 3 1000
aaaaa


Output


1009


Input


8 1
10 15 2 1 4 8 15 16
qqwweerr


Output


41


Input


6 3
14 18 9 19 2 15
cccccc


Output


52


Input


2 1
10 10
qq


Output


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.
import java.util.*;
import java.awt.List;
import java.io.*;
import java.lang.*;
import java.lang.reflect.Array;
public class c1 
{

	
	public static int mod = (int)Math.pow(10, 9) + 7;
   
	
    public static void main(String[] args)
    {
        InputReader in = new InputReader(System.in);
        PrintWriter pw = new PrintWriter(System.out);

        // Code starts..
        
        int n = in.nextInt();
        int k = in.nextInt();
        long[] a = new long[n];
        for(int i=0; i<n; i++)
        	a[i] = in.nextLong();
        
        String s = in.nextLine();
        PriorityQueue<Long> que = new PriorityQueue<>();
        long ans = 0;
        for(int i=0; i<n; i++)
        {
        	
        	if(i>0)
        	{
        		if(s.charAt(i)==s.charAt(i-1))
        		{
        			que.add(-a[i]);
        		}
        		else
        		{
        			for(int j=0; j<k && !que.isEmpty(); j++)
        			{	
        			//	pw.println(que.peek());
        				ans += -que.poll();
        			}
        			que.clear();
        			que.add(-a[i]);
        		}
        	}
        	else
        		que.add(-a[i]);
        //	pw.println(que);
        	
        }
    	for(int j=0; j<k && !que.isEmpty(); j++)
		{	
		//	pw.println(que.peek());
			ans += -que.poll();
		}
	
        pw.println(ans);
        
        
        // code ends...

        pw.flush();
        pw.close();
    }
    public static boolean flag = false;
    
  
    
    public static int lcs( char[] X, char[] Y, int m, int n ) 
    { 
      int L[][] = new int[m+1][n+1]; 
    
      for (int i=0; i<=m; i++) 
      { 
        for (int j=0; j<=n; j++) 
        { 
          if (i == 0 || j == 0) 
              L[i][j] = 0; 
          else if (X[i-1] == Y[j-1]) 
              L[i][j] = L[i-1][j-1] + 1; 
          else
              L[i][j] = Math.max(L[i-1][j], L[i][j-1]); 
          if(L[i][j]>=100)
        	  return 100;
        }
        
      } 
    return L[m][n]; 
    } 
    
   
    
    
    
    public static void factSieve(int[] fact, long n)
    {

        for (int i = 2; i <= n; i += 2)
            fact[i] = 2;

        for (int i = 3; i <= n; i += 2) {
            if (fact[i] == 0) {
                fact[i] = i;

                for (int j = i; (long) j * i <= n; j++) {
                    fact[(int) ((long) i * j)] = i;
                }
            }
        }

        /*
         * int k = 1000; while(k!=1) { System.out.print(a[k]+" "); k /= a[k];
         * 
         * }
         */
    }

    
    public static int gcd(int p2, int p22)
    {
        if (p2 == 0)
            return (int) p22;
        return gcd(p22 % p2, p2);
    }

    public static void nextGreater(long[] a, int[] ans)
    {

        Stack<Integer> stk = new Stack<>();
        stk.push(0);

        for (int i = 1; i < a.length; i++) {

            if (!stk.isEmpty()) {
                int s = stk.pop();
                while (a[s] < a[i]) {
                    ans[s] = i;
                    if (!stk.isEmpty())
                        s = stk.pop();
                    else
                        break;
                }
                if (a[s] >= a[i])
                    stk.push(s);
            }

            stk.push(i);

        }
        return;

    }

    public static void nextGreaterRev(long[] a, int[] ans)
    {

        int n = a.length;
        int[] pans = new int[n];
        Arrays.fill(pans, -1);
        long[] arev = new long[n];
        for (int i = 0; i < n; i++)
            arev[i] = a[n - 1 - i];

        Stack<Integer> stk = new Stack<>();
        stk.push(0);

        for (int i = 1; i < n; i++) 
        {

            if (!stk.isEmpty()) {
                int s = stk.pop();
                while (arev[s] < arev[i]) {
                    pans[s] = n - i - 1;
                    if (!stk.isEmpty())
                        s = stk.pop();
                    else
                        break;
                }
                if (arev[s] >= arev[i])
                    stk.push(s);
            }

            stk.push(i);

        }

        // for(int i=0; i<n; i++)
        // System.out.print(pans[i]+" ");

        for (int i = 0; i < n; i++)
            ans[i] = pans[n - i - 1];

        return;

    }

    public static void nextSmaller(long[] a, int[] ans)
    {

        Stack<Integer> stk = new Stack<>();
        stk.push(0);

        for (int i = 1; i < a.length; i++) {

            if (!stk.isEmpty()) {
                int s = stk.pop();
                while (a[s] > a[i]) {
                    ans[s] = i;
                    if (!stk.isEmpty())
                        s = stk.pop();
                    else
                        break;
                }
                if (a[s] <= a[i])
                    stk.push(s);
            }

            stk.push(i);

        }
        return;

    }

    public static long lcm(int[] numbers) 
    {
        long lcm = 1;
        int divisor = 2;
        while (true) {
            int cnt = 0;
            boolean divisible = false;
            for (int i = 0; i < numbers.length; i++) {
                if (numbers[i] == 0) {
                    return 0;
                } else if (numbers[i] < 0) {
                    numbers[i] = numbers[i] * (-1);
                }
                if (numbers[i] == 1) {
                    cnt++;
                }
                if (numbers[i] % divisor == 0) {
                    divisible = true;
                    numbers[i] = numbers[i] / divisor;
                }
            }
            if (divisible) {
                lcm = lcm * divisor;
            } else {
                divisor++;
            }
            if (cnt == numbers.length) {
                return lcm;
            }
        }
    }

    public static long fact(long n)
    {

        long factorial = 1;
        for (int i = 1; i <= n; i++) {
            factorial *= i;
        }
        return factorial;
    }


    public static long choose(long total, long choose)
    {
        if (total < choose)
            return 0;
        if (choose == 0 || choose == total)
            return 1;
        return (choose(total - 1, choose - 1) + choose(total - 1, choose)) % mod;
    }

    public static int[] suffle(int[] a, Random gen)
    {
        int n = a.length;
        for (int i = 0; i < n; i++) {
            int ind = gen.nextInt(n - i) + i;
            int temp = a[ind];
            a[ind] = a[i];
            a[i] = temp;
        }
        return a;
    }

    public static int[] sufflesort(int[] a) 
    {
        int n = a.length;
        Random gen = new Random();
        for (int i = 0; i < n; i++) {
            int ind = gen.nextInt(n - i) + i;
            int temp = a[ind];
            a[ind] = a[i];
            a[i] = temp;
        }
        Arrays.sort(a);
        return a;
    }
    
    
    
    
    public static int floorSearch(int arr[], int low, int high, int x) 
    {
        if (low > high)
            return -1;

        if (x > arr[high])
            return high;
        int mid = (low + high) / 2;

        if (mid > 0 && arr[mid - 1] < x && x < arr[mid])
            return mid - 1;

        if (x < arr[mid])
            return floorSearch(arr, low, mid - 1, x);

        return floorSearch(arr, mid + 1, high, x);
    }

    public static void swap(int a, int b) {
        int temp = a;
        a = b;
        b = temp;
    }

    public static ArrayList<Integer> primeFactorization(int n)
    {
        ArrayList<Integer> a = new ArrayList<Integer>();
        for (int i = 2; i * i <= n; i++) {
            while (n % i == 0) {
                a.add(i);
                n /= i;
            }
        }
        if (n != 1)
            a.add(n);
        return a;
    }
    
    
    

    public static void sieve(boolean[] isPrime, int n) 
    {
        for (int i = 1; i < n; i++)
            isPrime[i] = true;

        isPrime[0] = false;
        isPrime[1] = false;

        for (int i = 2; i * i < n; i++) {
            if (isPrime[i] == true) {
                for (int j = (2 * i); j < n; j += i)
                    isPrime[j] = false;
            }
        }
    }

    public static int lowerbound(ArrayList<Long> net, long c2) 
    {
        int i = Collections.binarySearch(net, c2);
        if (i < 0)
            i = -(i + 2);
        return i;

    }
    
    public static int lowerboundArray(int[] dis, int c2) 
    {
        int i = Arrays.binarySearch(dis, c2);
        
        if (i < 0)
            i = -(i + 2);
        return i;

    }

    public static int uperbound(ArrayList<Integer> list, int c2) 
    {
        int i = Collections.binarySearch(list, c2);
        if (i < 0)
            i = -(i + 1);
        return i;

    }

    public static int uperboundArray(int[] dis, int c2)
    {
        int i = Arrays.binarySearch(dis, c2);
        if (i < 0)
            i = -(i + 1);
        return i;

    }

    
    public static int GCD(int a, int b)
    {
        if (b == 0)
            return a;
        else
            return GCD(b, a % b);
    }

    public static long GCD(long a, long b) 
    {
        if (b == 0)
            return a;
        else
            return GCD(b, a % b);
    }

    public static int d1;
    public static int p1;
    public static int q1;
    
    public static void extendedEuclid(int A, int B)
    {
        if (B == 0) {
            d1 = A;
            p1 = 1;
            q1 = 0;
        } else {
            extendedEuclid(B, A % B);
            int temp = p1;
            p1 = q1;
            q1 = temp - (A / B) * q1;
        }
    }

    public static long LCM(long a, long b) {
        return (a * b) / GCD(a, b);
    }

    public static int LCM(int a, int b) {
        return (a * b) / GCD(a, b);
    }

    public static int binaryExponentiation(int x, int n) {
        int result = 1;
        while (n > 0) {
            if (n % 2 == 1)
                result = result * x;
            x = x * x;
            n = n / 2;
        }
        return result;
    }

    public static int[] countDer(int n) {
        int der[] = new int[n + 1];

        der[0] = 1;
        der[1] = 0;
        der[2] = 1;

        for (int i = 3; i <= n; ++i)
            der[i] = (i - 1) * (der[i - 1] + der[i - 2]);

        // Return result for n
        return der;
    }

    static long binomialCoeff(int n, int k) {
        long C[][] = new long[n + 1][k + 1];
        int i, j;

        // Calculate value of Binomial Coefficient in bottom up manner
        for (i = 0; i <= n; i++) {
            for (j = 0; j <= Math.min(i, k); j++) {
                // Base Cases
                if (j == 0 || j == i)
                    C[i][j] = 1;

                // Calculate value using previosly stored values
                else
                    C[i][j] = C[i - 1][j - 1] + C[i - 1][j];
            }
        }

        return C[n][k];
    }

    public static long binaryExponentiation(long x, long n) {
        long result = 1;
        while (n > 0) {
            if (n % 2 == 1)
                result = result * x;
            x = (x % mod * x % mod) % mod;
            n = n / 2;
        }
        return result;
    }

    public static int modularExponentiation(int x, int n, int M) {
        int result = 1;
        while (n > 0) {
            if (n % 2 == 1)
                result = (result * x) % M;
            x = (x * x) % M;
            n = n / 2;
        }
        return result;
    }

    public static long modularExponentiation(long x, long n, long M) {
        long result = 1;
        while (n > 0) {
            if (n % 2 == 1)
                result = (result * x) % M;
            x = (x * x) % M;
            n = n / 2;
        }
        return result;
    }

    public static int modInverse(int A, int M) {
        return modularExponentiation(A, M - 2, M);
    }

    public static long sie(long A, long M) {
        return modularExponentiation(A, M - 2, M);
    }

    public static boolean isPrime(int n) {

        if (n <= 1)
            return false;
        if (n <= 3)
            return true;

        if (n % 2 == 0 || n % 3 == 0)
            return false;

        for (int i = 5; i * i <= n; i = i + 6) {
            if (n % i == 0 || n % (i + 2) == 0)
                return false;
        }

        return true;
    }

    static class pair implements Comparable<pair>

    {
        Integer x, y;

        pair(int x, int y) {
            this.x = x;
            this.y = y;
        }

        public int compareTo(pair o) {
            int result = x.compareTo(o.x);
            if (result == 0)
                result = y.compareTo(o.y);

            return result;
        }

        public String toString() {
            return x + " " + y;
        }

        public boolean equals(Object o) {
            if (o instanceof pair) {
                pair p = (pair) o;
                return p.x == x && p.y == y;
            }
            return false;
        }

        public int hashCode() {
            return new Long(x).hashCode() * 31 + new Long(y).hashCode();
        }

    }

    static class tripletD implements Comparable<tripletD>

    {
        Double x, y, z;

        tripletD(double x, double y, double z) {
            this.x = x;
            this.y = y;
            this.z = z;
        }

        public int compareTo(tripletD o) {
            int result = x.compareTo(o.x);
            if (result == 0)
            {
            	double x1 = o.x + o.y;
            	result = ((Double)x1).compareTo((double)(x+y));
            }

            return result;
        }

        public String toString() {
            return x + " " + y+" "+z;
        }

        public boolean equals(Object o) {
            if (o instanceof tripletD) {
            	tripletD p = (tripletD) o;
                return p.x == x && p.y == y && p.z == z;
            }
            return false;
        }

        public int hashCode() {
            return new Double(x).hashCode() * 31 + new Double(y).hashCode();
        }

    }

    static class triplet implements Comparable<triplet> {
        Integer x, y, z;

        triplet(int x, int y, int z) {
            this.x = x;
            this.y = y;
            this.z = z;
        }

        public int compareTo(triplet o) {
            int result = x.compareTo(o.x);
            if (result == 0)
                result = y.compareTo(o.y);
            if (result == 0)
                result = z.compareTo(o.z);

            return result;
        }

        public boolean equlas(Object o) {
            if (o instanceof triplet) {
                triplet p = (triplet) o;
                return x == p.x && y == p.y && z == p.z;
            }
            return false;
        }

        public String toString() {
            return x + " " + y + " " + z;
        }

        public int hashCode() {
            return new Long(x).hashCode() * 31 + new Long(y).hashCode() + new Long(z).hashCode();
        }
    }

    
    
    
    
    
    /*
     * static class node implements Comparable<node>
     * 
     * { Integer x, y, z; node(int x,int y, int z) { this.x=x; this.y=y; this.z=z; }
     * 
     * public int compareTo(pair o) { int result = x.compareTo(o.x); if(result==0)
     * result = y.compareTo(o.y); if(result==0) result = z.compareTo(z); return
     * result; }
     * 
     * @Override public int compareTo(node o) { // TODO Auto-generated method stub
     * return 0; } }
     */



    static class InputReader 
	{
		 
		private final InputStream stream;
		private final byte[] buf = new byte[8192];
		private int curChar, snumChars;
		private SpaceCharFilter filter;
 
		public InputReader(InputStream stream) 
		{
			this.stream = stream;
		}
 
		public int snext() 
		{
			if (snumChars == -1)
				throw new InputMismatchException();
			if (curChar >= snumChars) 
			{
				curChar = 0;
				try 
				{
					snumChars = stream.read(buf);
				} 
				catch (IOException e) 
				{
					throw new InputMismatchException();
				}
				if (snumChars <= 0)
					return -1;
			}
			return buf[curChar++];
		}
 
		public int nextInt() 
	    {
			int c = snext();
			while (isSpaceChar(c)) 
			{
				c = snext();
			}
			int sgn = 1;
			if (c == '-')
		    {
				sgn = -1;
				c = snext();
			}
			int res = 0;
			do 
			{
				if (c < '0' || c > '9')
					throw new InputMismatchException();
				res *= 10;
				res += c - '0';
				c = snext();
			} while (!isSpaceChar(c));
			return res * sgn;
		}
 
		public long nextLong()
	    {
			int c = snext();
			while (isSpaceChar(c)) 
			{
				c = snext();
			}
			int sgn = 1;
			if (c == '-') 
			{
				sgn = -1;
				c = snext();
			}
			long res = 0;
			do 
			{
				if (c < '0' || c > '9')
					throw new InputMismatchException();
				res *= 10;
				res += c - '0';
				c = snext();
			} while (!isSpaceChar(c));
			return res * sgn;
		}
 
		public int[] nextIntArray(int n) 
		{
			int a[] = new int[n];
			for (int i = 0; i < n; i++) 
			{
				a[i] = nextInt();
			}
			return a;
		}
 
		public String readString()
	    {
			int c = snext();
			while (isSpaceChar(c)) 
			{
				c = snext();
			}
			StringBuilder res = new StringBuilder();
			do 
			{
				res.appendCodePoint(c);
				c = snext();
			} while (!isSpaceChar(c));
			return res.toString();
		}
 
		public String nextLine() 
		{
			int c = snext();
			while (isSpaceChar(c))
				c = snext();
			StringBuilder res = new StringBuilder();
			do 
			{
				res.appendCodePoint(c);
				c = snext();
			} while (!isEndOfLine(c));
			return res.toString();
		}
 
		public boolean isSpaceChar(int c) 
		{
			if (filter != null)
				return filter.isSpaceChar(c);
			return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
		}
 
		private boolean isEndOfLine(int c) 
		{
			return c == '\n' || c == '\r' || c == -1;
		}
 
		public interface SpaceCharFilter
	    {
			public boolean isSpaceChar(int ch);
		}
	}
	
	



}

