package main

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

func main() {
	var N, v int
	fmt.Scan(&N)
	A := make([]int, N)
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)
	sum := 0
	for i := range A {
		sc.Scan()
		A[i], _ = strconv.Atoi(sc.Text())
		sum += A[i]
	}
	fmt.Scan(&v)
	fmt.Println(sum - v)

}