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.io.*;
import java.util.*;
import java.text.*;
import java.math.*;
import java.util.regex.*;


 
public class TryC
{
    
    static class InputReader {
 
		private final InputStream stream;
		private final byte[] buf = new byte[8192];
		private int curChar, snumChars;
 
		public InputReader(InputStream st) {
			this.stream = st;
		}
 
		public int read() {
			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 ni() {
			int c = read();
			while (isSpaceChar(c)) {
				c = read();
			}
			int sgn = 1;
			if (c == '-') {
				sgn = -1;
				c = read();
			}
			int res = 0;
			do {
				res *= 10;
				res += c - '0';
				c = read();
			} while (!isSpaceChar(c));
			return res * sgn;
		}
 
		public long nl() {
			int c = read();
			while (isSpaceChar(c)) {
				c = read();
			}
			int sgn = 1;
			if (c == '-') {
				sgn = -1;
				c = read();
			}
			long res = 0;
			do {
				res *= 10;
				res += c - '0';
				c = read();
			} while (!isSpaceChar(c));
			return res * sgn;
		}
 
		public int[] nia(int n) {
			int a[] = new int[n];
			for (int i = 0; i < n; i++) {
				a[i] = ni();
			}
			return a;
		}
 
		public String rs() {
			int c = read();
			while (isSpaceChar(c)) {
				c = read();
			}
			StringBuilder res = new StringBuilder();
			do {
				res.appendCodePoint(c);
				c = read();
			} while (!isSpaceChar(c));
			return res.toString();
		}
 
		public String nextLine() {
			int c = read();
			while (isSpaceChar(c))
				c = read();
			StringBuilder res = new StringBuilder();
			do {
				res.appendCodePoint(c);
				c = read();
			} while (!isEndOfLine(c));
			return res.toString();
		}
 
		public boolean isSpaceChar(int c) {
			return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
		}
 
		private boolean isEndOfLine(int c) {
			return c == '\n' || c == '\r' || c == -1;
		}
 
	}
	

	
	
	
    static long mod=1000000007;
    static BigInteger bigInteger = new BigInteger("1000000007");
    static int n = (int)1e6;
    static boolean[] prime;
    static ArrayList<Integer> as;
     static ArrayList<Integer> []as1;
    static void sieve() {
			Arrays.fill(prime	, true);
			prime[0] = prime[1] = false;
			for(int i = 2 ; i * i <= n ; ++i) {
				if(prime[i]) {
					for(int k = i * i; k< n ; k+=i) {
						prime[k] = false;
					}
				}
			}
			
		}
		static PrintWriter w = new PrintWriter(System.out);
                static int p = 0;
 static char [][]sol;
    public static void main(String[] args)
    {
        
        InputReader sc = new InputReader(System.in);
        //PrintWriter w = new PrintWriter(System.out);
    
        
        prime  = new boolean[n + 1];
		sieve();
		prime[1] = false;
		
		/*
		as = new ArrayList<>();
		for(int i=2;i<=1000000;i++)
		{
		    if(prime[i])
		    as.add(i);
		}
		*/
		
       /* 
		
	long a = sc.nl();
	 
            BigInteger ans = new BigInteger("1");
            for (long i = 1; i < Math.sqrt(a); i++) {
                if (a % i == 0) {
                    if (a / i == i) {
                        ans = ans.multiply(BigInteger.valueOf(phi(i)));
                        
                    } else {
                        ans = ans.multiply(BigInteger.valueOf(phi(i)));
                        ans = ans.multiply(BigInteger.valueOf(phi(a / i)));
 
                        
                    }
 
 
                }
            }
            w.println(ans.mod(bigInteger));
            */
          
         // MergeSort ob = new MergeSort();
       // ob.sort(arr, 0, arr.length-1);
       
    // Student []st = new Student[x];    
   // st[i] = new Student(i,d[i]);
     //Arrays.sort(st,(p,q)->p.diff-q.diff);
     
 int x = sc.ni();
 int k = sc.ni();
 long res = 0;
 int []a = sc.nia(x);
 String s = sc.rs();
 char prev = s.charAt(0);
 TreeSet<Integer> ts = new TreeSet<>();
 ts.add(a[0]);
 int c = 1;
 HashMap<Integer,Integer> hm = new HashMap<>();
hm.put(a[0], 1);
 for(int i=1;i<x;i++)
 {
     if(prev == s.charAt(i))
     {
         c++;
         ts.add(a[i]);
         prev = s.charAt(i);
         if(!hm.containsKey(a[i]))
             hm.put(a[i], 1);
         else
             hm.put(a[i], hm.get(a[i])+1);
     }
     else
     {
         int p = Math.min(k, c);
         while(p-- > 0)
         {
             res += (long) ts.last();
             
             hm.put(ts.last(), hm.get(ts.last())-1);
             if(hm.get(ts.last())==0)
             ts.remove(ts.last());
            // p--;
         }
         ts.clear();
         
         ts.add(a[i]);
         c = 1;
         prev = s.charAt(i);
         hm = new HashMap<>();
         hm.put(a[i], 1);
     }
 }
  int p = Math.min(k, c);
         while(p-- > 0)
         {
             res += (long) ts.last();
              hm.put(ts.last(), hm.get(ts.last())-1);
             if(hm.get(ts.last())==0)
             ts.remove(ts.last());
             //p--;
         }
 
 w.println(res);
  
   w.close();
        
  
    
    }
    static long log2(long value) {
    return Long.SIZE-Long.numberOfLeadingZeros(value);
}
   
     static class Student
    {
        
        int first;
        int sec;
        int index;
        Student(int first,int sec,int index)
        {
            this.first = first;
            this.sec = sec;
            this.index = index;             
            
        }
        
    }
     
     public static long modMultiply(long one, long two) {
 
		return (one % mod * two % mod) % mod;
	}
    static long fx(int m)
    {
        long re = 0;
        for(int i=1;i<=m;i++)
        {
            re += (long) (i / gcd(i,m));
        }
        return re;
    }
     static int gcd(int a, int b)
    {
	 if (a == 0)
	  return b;
				         
	return gcd(b%a, a);
    }
    
   
    
     static long phi(long nx)
    {
        // Initialize result as n
        double result = nx; 
        
     
        // Consider all prime factors of n and for 
        // every prime factor p, multiply result
        // with (1 - 1/p)
        for (int p = 0; as.get(p) * as.get(p) <= nx; ++p)
        {
            // Check if p is a prime factor.
            if (nx % as.get(p) == 0)
            {
                // If yes, then update n and result
                while (nx % as.get(p) == 0)
                    nx /= as.get(p);
                result *= (1.0 - (1.0 / (double) as.get(p)));
            }
        }
     
        // If n has a prime factor greater than sqrt(n)
        // (There can be at-most one such prime factor)
        if (nx > 1)
            result *= (1.0 - (1.0 / (double) nx));
     
        return (long)result;
    
        
        //return(phi((long)result,k-1));
        
    }
    
    public static void primeFactors(int n,int x)
    {
        as = new ArrayList<>();
       
        // Print the number of 2s that divide n
        while (n%2==0)
        {
            
        
            as.add(2);
            //System.out.print(2 + " ");
            n /= 2;
            
        }
 
        // n must be odd at this point.  So we can
        // skip one element (Note i = i +2)
        for (int i = 3; i <= Math.sqrt(n); i+= 2)
        {
            // While i divides n, print i and divide n
            while (n%i == 0)
            {
            
               // System.out.print(i + " ");
                
                as.add(i);
                n /= i;
             
                
            }
            
        }
 
        // This condition is to handle the case whien
        // n is a prime number greater than 2
        if (n >= 2)
        {
          
            as.add(n);
        }
           
    }
    static int digitsum(int x)
    
    {    
 
        int sum = 0;
        while(x > 0)
        {
            int temp = x % 10;
            sum += temp;
            x /= 10;
        }
        return sum;
        
    }
    static int countDivisors(int n)
    {
        int cnt = 0;
        for (int i = 1; i*i <=n; i++)
        {
             if (n % i == 0 && i<=1000000)
             {
                // If divisors are equal,
                // count only one
                if (n / i == i)
                   cnt++;
      
                else // Otherwise count both
                    cnt = cnt + 2;
             }
         }
        return cnt;
    }
   
    static boolean isprime(long n)
    {
    
    if(n == 2)
        return true;
    if(n == 3)
        return true;
    if(n % 2 == 0)
        return false;
    if(n % 3 == 0)
        return false;
 
    long i = 5;
   long w = 2;
 
    while(i * i <= n)
    {
        if(n % i == 0)
            return false;
    
 
        i += w;
        w = 6 - w;
    }
 
    return true;
    }
    
   
 
 
    
    
    static boolean binarysearch(int []arr,int p,int n)
    {
        //ArrayList<Integer> as = new ArrayList<>();
        //as.addAll(0,at);
        //Collections.sort(as);
        boolean re = false;
        int st = 0;
        int end = n-1;
        
        
        
        while(st <= end)
        { 
            int mid = (st+end)/2;
        
            if(p > arr[mid])
            {
                st = mid+1;
                
            }
            else if(p < arr[mid])
            {
                end = mid-1;
                
            }
            else if(p == arr[mid])
            {
            
            re = true;
            break;
            }
           
            
            
        }
         return re;
        
    }
    
   
    
    /* Java program for Merge Sort */
static class MergeSort
{
    // Merges two subarrays of arr[].
    // First subarray is arr[l..m]
    // Second subarray is arr[m+1..r]
    void merge(int arr[], int l, int m, int r)
    {
        // Find sizes of two subarrays to be merged
        int n1 = m - l + 1;
        int n2 = r - m;
 
        /* Create temp arrays */
        int L[] = new int [n1];
        int R[] = new int [n2];
 
        /*Copy data to temp arrays*/
        for (int i=0; i<n1; ++i)
            L[i] = arr[l + i];
        for (int j=0; j<n2; ++j)
            R[j] = arr[m + 1+ j];
 
 
        /* Merge the temp arrays */
 
        // Initial indexes of first and second subarrays
        int i = 0, j = 0;
 
        // Initial index of merged subarry array
        int k = l;
        while (i < n1 && j < n2)
        {
            if (L[i] <= R[j])
            {
                arr[k] = L[i];
                i++;
            }
            else
            {
                arr[k] = R[j];
                j++;
            }
            k++;
        }
 
        /* Copy remaining elements of L[] if any */
        while (i < n1)
        {
            arr[k] = L[i];
            i++;
            k++;
        }
 
        /* Copy remaining elements of R[] if any */
        while (j < n2)
        {
            arr[k] = R[j];
            j++;
            k++;
        }
    }
 
    // Main function that sorts arr[l..r] using
    // merge()
    void sort(int arr[], int l, int r)
    {
        if (l < r)
        {
            // Find the middle point
            int m = (l+r)/2;
 
            // Sort first and second halves
            sort(arr, l, m);
            sort(arr , m+1, r);
 
            // Merge the sorted halves
            merge(arr, l, m, r);
        }
    }
 
    /* A utility function to print array of size n */
    
 
   
}
    

    
    
    
    public static int ip(String s){
		return Integer.parseInt(s);
	}
	 public static String ips(int s){
		return Integer.toString(s);
	}
	
         // Java program to print all permutations using
// Heap's algorithm
static class HeapAlgo
{
   //static ArrayList<Integer> []ad;
	//Prints the array
	void printArr(int a[], int n)
	{
	    
	    
		for (int i=0; i<n; i++)
		{
			System.out.print(a[i] + " ");
		as1[p].add(a[i]);
		}
                p++;
                
		//System.out.println();
	}

	//Generating permutation using Heap Algorithm
	void heapPermutation(int a[], int size, int n)
	{
		// if size becomes 1 then prints the obtained
		// permutation
		
		if (size == 1)
		{
			printArr(a,n);
			
		}

		for (int i=0; i<size; i++)
		{
			heapPermutation(a, size-1, n);
                        p++;

			// if size is odd, swap first and last
			// element
			if (size % 2 == 1)
			{
				int temp = a[0];
				a[0] = a[size-1];
				a[size-1] = temp;
			}

			// If size is even, swap ith and last
			// element
			else
			{
				int temp = a[i];
				a[i] = a[size-1];
				a[size-1] = temp;
			}
		}
	}
        public static int lowerBound(int[] array, int length, int value) {
        int low = 0;
        int high = length-1;
        while (low < high) {
            final int mid = (low + high) / 2;
            if (value <= array[mid]) {
                high = mid;
            } else {
                low = mid + 1;
            }
        }
        return low;
  }
  public static int upperBound(int[] array, int length, int value) {
        int low = 0;
        int high = length-1;
        while (low < high) {
            final int mid = (low + high) / 2;
            if (value >= array[mid]) {
                low = mid + 1;
            } else {
                high = mid;
            }
        }
        return low;
    }

	// Driver code
	
		
	
}

// This code has been contributed by Amit Khandelwal.

    
					 
}