package main

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

func main() {
	var N, a, A, v int
	N = nextInt()
	for i:=0; i<N; i++{
		a = nextInt()
		A += a
	}
	v = nextInt()
	fmt.Println(A-v)
}

var s = bufio.NewScanner(os.Stdin)

func next() string {
	s.Split(bufio.ScanWords)
	s.Scan()
	return s.Text()
}

func nextInt() int {
	i, e := strconv.Atoi(next())
	if e != nil {
		panic(e)
	}
	return i
}