# -*- coding: utf-8 -*-
"""
No.549 素材合成システム
https://yukicoder.me/problems/no/549

"""
import sys
from sys import stdin
input = stdin.readline


def solve(androids):
    androids.sort(reverse=True)
    ans = androids[0]
    for a in androids[1:]:
        ans += a // 2
    return ans


def main(args):
    N = int(input())
    androids = [int(x) for x in input().split()]
    ans = solve(androids)
    print(ans)


if __name__ == '__main__':
    main(sys.argv[1:])