package main
import (
"fmt"
"sort"
)
func main() {
var n int
var k int64
fmt.Scan(&n, &k)
a := make([]int, n)
for i := 0; i < n; i++ {
fmt.Scan(&a[i])
}
var s string
fmt.Scan(&s)
realprice := make([]int64, n)
for i := 0; i < n; i++ {
if s[i] == '1' {
realprice[i] = int64(a[i]) * 95
} else {
realprice[i] = int64(a[i]) * 100
}
}
sort.Slice(realprice, func(i, j int) bool {
return realprice[i] < realprice[j]
})
count := 0
var sum int64 = 0 // 3. 累计和必须是 int64
limit := k * 100
for i := 0; i < n; i++ {
if sum + realprice[i] <= limit {
sum += realprice[i]
count++
} else {
break
}
}
fmt.Print(count)
}