package main

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

func mapToInt(arr []string) []int {
	ret := make([]int, len(arr))
	var err error
	for i := 0; i < len(arr); i++ {
		ret[i], err = strconv.Atoi(arr[i])
		if err != nil {
			panic(err)
		}
	}
	return ret
}

func main() {
	scanner := bufio.NewScanner(os.Stdin)
	var N int
	var v int

	scanner.Scan()
	N, _ = strconv.Atoi(scanner.Text())
	scanner.Scan()
	A := mapToInt(strings.Split(scanner.Text(), " "))
	scanner.Scan()
	v, _ = strconv.Atoi(scanner.Text())

	if !(1 <= N && N <= 10000) {
		panic("")
	}

	if len(A) != N {
		panic("")
	}

	sum := 0
	for i := 0; i < N; i++ {
		if !(-10000 <= A[i] && A[i] <= 10000) {
			panic("")
		}
		sum += A[i]
	}
	fmt.Println(sum - v)

}