package main

import (
	"bufio"
	"fmt"
	"os"
	"strconv"
)

func configure(scanner *bufio.Scanner) {
	scanner.Split(bufio.ScanWords)
	scanner.Buffer(make([]byte, 1000005), 1000005)
}
func getNextString(scanner *bufio.Scanner) string {
	scanned := scanner.Scan()
	if !scanned {
		panic("scan failed")
	}
	return scanner.Text()
}
func getNextInt(scanner *bufio.Scanner) int {
	i, _ := strconv.Atoi(getNextString(scanner))
	return i
}
func getNextInt64(scanner *bufio.Scanner) int64 {
	i, _ := strconv.ParseInt(getNextString(scanner), 10, 64)
	return i
}
func getNextFloat64(scanner *bufio.Scanner) float64 {
	i, _ := strconv.ParseFloat(getNextString(scanner), 64)
	return i
}
func main() {
	fp := os.Stdin
	wfp := os.Stdout
	cnt := 1
	if os.Getenv("I") == "IronMan" {
		fp, _ = os.Open(os.Getenv("END_GAME"))
		cnt = 100
	}
	scanner := bufio.NewScanner(fp)
	configure(scanner)
	writer := bufio.NewWriter(wfp)
	defer func() {
		r := recover()
		if r != nil {
			fmt.Fprintln(writer, r)
		}
		writer.Flush()
	}()
	for i := 0; i < cnt; i++ {
		if i > 0 {
			fmt.Fprintln(writer, "-----------------------------------")
		}
		solve(scanner, writer)
	}
}
func solve(scanner *bufio.Scanner, writer *bufio.Writer) {
	n := getNextInt(scanner)
	c := getNextInt(scanner)
	bb := make([]bamboo, n)
	for i := 0; i < n; i++ {
		bb[i].l = getNextInt(scanner)
	}
	for i := 0; i < n; i++ {
		bb[i].w = getNextInt(scanner)
	}
	var dp [51][51][51]int
	for i := 0; i < n; i++ {
		for j := 0; j < n; j++ {
			if bb[i].l == bb[j].l {
				continue
			}
			if bb[i].w+bb[j].w > c {
				continue
			}
			dp[bb[i].l][bb[j].l][bb[i].w+bb[j].w] = bb[i].l + bb[j].l
		}
	}
	updated := true
	var ans int
	for updated == true {
		updated = false
		for i := 0; i < n; i++ {
			for j := 0; j < bb[i].l; j++ {
				for k := j + 1; k < 51; k++ {
					for l := 0; l+bb[i].w <= c; l++ {
						if dp[j][k][l] == 0 {
							continue
						}
						if k == bb[i].l {
							continue
						}
						if dp[bb[i].l][j][l+bb[i].w] < dp[j][k][l]+bb[i].l {
							dp[bb[i].l][j][l+bb[i].w] = dp[j][k][l] + bb[i].l
							if ans < dp[bb[i].l][j][l+bb[i].w] {
								ans = dp[bb[i].l][j][l+bb[i].w]
							}
							updated = true
						}
					}
				}
			}
			for j := bb[i].l + 1; j < 51; j++ {
				for k := 0; k < j; k++ {
					for l := 0; l+bb[i].w <= c; l++ {
						if dp[j][k][l] == 0 {
							continue
						}
						if k == bb[i].l {
							continue
						}
						if dp[bb[i].l][j][l+bb[i].w] < dp[j][k][l]+bb[i].l {
							dp[bb[i].l][j][l+bb[i].w] = dp[j][k][l] + bb[i].l
							if ans < dp[bb[i].l][j][l+bb[i].w] {
								ans = dp[bb[i].l][j][l+bb[i].w]
							}
							updated = true
						}
					}
				}
			}
		}
	}
	fmt.Fprintln(writer, ans)
}

type bamboo struct {
	l, w int
}