package main

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

func main() {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)

	n := scanInt(sc)

	f := 0
	for i := 0; i < len(ns); i++ {
		f += scanInt(sc) - 1
	}

	fmt.Println(f)
}

func scanInt(sc *bufio.Scanner) int {
	sc.Scan()
	v, _ := strconv.Atoi(sc.Text())
	return v
}
