You are at a water bowling training. There are *l* people who play with their left hand, *r* people, who play with their right hand, and *a* ambidexters, who can play with left or right hand.

The coach decided to form a team of even number of players, exactly half of the players should play with their right hand, and exactly half of the players should play with their left hand. One player should use only on of his hands.

Ambidexters play as well with their right hand as with their left hand. In the team, an ambidexter can play with their left hand, or with their right hand.

Please find the maximum possible size of the team, where equal number of players use their left and right hands, respectively.
The only line contains three integers *l*, *r* and *a* (0 ≤ *l*, *r*, *a* ≤ 100) — the number of left-handers, the number of right-handers and the number of ambidexters at the training.
In the first example you can form a team of 6 players. You should take the only left-hander and two ambidexters to play with left hand, and three right-handers to play with right hand. The only person left can't be taken into the team.

In the second example you can form a team of 14 people. You have to take all five left-handers, all five right-handers, two ambidexters to play with left hand and two ambidexters to play with right hand.
1 4 2
6
5 5 5
14
0 2 0
0
30 70 34
128
89 32 24
112
89 44 77
210
0 0 0
0
100 100 100
300
1 1 1
2
30 70 35
130
89 44 76
208
0 100 100
200
100 0 100
200
100 1 100
200
1 100 100
200
100 100 0
200
100 100 1
200
1 2 1
4
0 0 100
100
0 100 0
0
100 0 0
0
10 8 7
24
45 47 16
108
59 43 100
202
34 1 30
62
14 81 1
30
53 96 94
242
62 81 75
218
21 71 97
188
49 82 73
204
88 19 29
96
89 4 62
132
58 3 65
126
27 86 11
76
35 19 80
134
4 86 74
156
32 61 89
182
68 60 98
226
37 89 34
142
92 9 28
74
79 58 98
234
35 44 88
166
16 24 19
58
74 71 75
220
83 86 99
268
97 73 15
176
77 76 73
226
48 85 55
188
1 2 2
4
2 2 2
6
2 1 2
4
2 2 1
4
3 2 1
6
1 2 3
6
1 3 2
6
2 1 3
6
2 3 1
6
3 1 2
6
99 99 99
296
99 99 100
298
99 100 99
298
99 100 100
298
100 99 99
298
100 99 100
298
100 100 99
298
89 32 23
110
4 5 0
8
3 0 3
6
0 0 2
2
97 97 0
194
1 4 0
2
5 2 0
4
0 5 10
14
0 1 2
2
5 2 3
10
5 5 0
10
0 0 10
10
0 1 1
2
0 0 1
0
l,r,a = map(int,input().split(" "))

while a > 0:
    if(l<r):
        l += 1
    else:
        r += 1
    a -= 1
print(min(l,r)*2)