package main

import (
	"fmt"
	"sort"
)

func main() {
    var n,k int
    fmt.Scan(&n,&k)
    g := make([]float64,n)
    for i:=0;i<n;i++{
        fmt.Scan(&g[i])
    }
    var str string
    fmt.Scan(&str)
    for i,v := range str{
        if v == '1'{
            g[i] *=0.95 
        }
    }
    sort.Float64s(g)
    num := 0
    total := 0.0
    for _,v := range g{
        total += v
        if total<=float64(k){
            num +=1
        }
    }
    fmt.Print(num)
}