list=[]
i = int(input())
list=[int(a) for a in input().split()]
max=max(list)
while max*i/2 -sum(list)<=0:
max+=1
print(max)1472B - Fair Division | 1281C - Cut and Paste |
141A - Amusing Joke | 112A - Petya and Strings |
677A - Vanya and Fence | 1621A - Stable Arrangement of Rooks |
472A - Design Tutorial Learn from Math | 1368A - C+= |
450A - Jzzhu and Children | 546A - Soldier and Bananas |
32B - Borze | 1651B - Prove Him Wrong |
381A - Sereja and Dima | 41A - Translation |
1559A - Mocha and Math | 832A - Sasha and Sticks |
292B - Network Topology | 1339A - Filling Diamonds |
910A - The Way to Home | 617A - Elephant |
48A - Rock-paper-scissors | 294A - Shaass and Oskols |
1213A - Chips Moving | 490A - Team Olympiad |
233A - Perfect Permutation | 1360A - Minimal Square |
467A - George and Accommodation | 893C - Rumor |
227B - Effective Approach | 1534B - Histogram Ugliness |