#!/bin/python3

import sys

def longestSequence(a):
    #  Return the length of the longest possible sequence of moves.
    moves = 0
    for i in a:
        if(i % 2 == 0):
            moves = moves + (i * 2 - 2)
        elif(i == 1):
            moves = moves + i
        else:
            moves = moves + (i + 1)
    return(moves)

if __name__ == "__main__":
    n = int(input().strip())
    a = list(map(int, input().strip().split(' ')))
    result = longestSequence(a)
    print(result)