package main import ( "bufio" "fmt" "os" "sort" "strconv" ) func appendSorted(a []int, b int) []int { i := sort.Search(len(a), func(i int) bool { return a[i] >= b }) a = append(a, 0) copy(a[i+1:], a[i:len(a)-1]) a[i] = b return a } func main() { defer flush() N := readInt() a := make([]int, N) for i := 0; i < N; i++ { a[i] = readInt() } b := make([]int, N) for i := 0; i < N; i++ { b[i] = readInt() } sort.Ints(a) t0 := make([]int, 0, N) t1 := make([]int, 0, 5000) result := 0 for i := 0; i < N; i++ { result += sort.Search(len(t0), func(j int) bool { return t0[j] >= a[i] }) t1 = appendSorted(t1, b[i]) result += sort.Search(len(t1), func(j int) bool { return t1[j] >= a[i] }) if len(t1) == 5000 { t0 = append(t0, t1...) sort.Ints(t0) t1 = t1[:0] } } println(result) } const ( ioBufferSize = 1 * 1024 * 1024 // 1 MB ) var stdinScanner = func() *bufio.Scanner { result := bufio.NewScanner(os.Stdin) result.Buffer(make([]byte, ioBufferSize), ioBufferSize) result.Split(bufio.ScanWords) return result }() func readString() string { stdinScanner.Scan() return stdinScanner.Text() } func readInt() int { result, err := strconv.Atoi(readString()) if err != nil { panic(err) } return result } var stdoutWriter = bufio.NewWriter(os.Stdout) func flush() { stdoutWriter.Flush() } func println(args ...interface{}) (int, error) { return fmt.Fprintln(stdoutWriter, args...) }