### 制約

• 0 \leq A,B,C \leq 10^9
• A,B,C は整数である

### 入力

A B C


### 入力例 1

3 1 4


### 出力例 1

5


• 毒入りの美味しいクッキー
• 解毒剤入りの美味しくないクッキー
• 毒入りの美味しいクッキー
• 解毒剤入りの美味しいクッキー
• 毒入りの美味しいクッキー
• 解毒剤入りの美味しくないクッキー
• 毒入りの美味しいクッキー

### 入力例 2

5 2 9


### 出力例 2

10


### 入力例 3

8 8 1


### 出力例 3

9


Score : 200 points

### Problem Statement

Takahashi has A untasty cookies containing antidotes, B tasty cookies containing antidotes and C tasty cookies containing poison.

Eating a cookie containing poison results in a stomachache, and eating a cookie containing poison while having a stomachache results in a death. As he wants to live, he cannot eat one in such a situation. Eating a cookie containing antidotes while having a stomachache cures it, and there is no other way to cure stomachaches.

Find the maximum number of tasty cookies that Takahashi can eat.

### Constraints

• 0 \leq A,B,C \leq 10^9
• A,B and C are integers.

### Input

Input is given from Standard Input in the following format:

A B C


### Output

Print the maximum number of tasty cookies that Takahashi can eat.

### Sample Input 1

3 1 4


### Sample Output 1

5


We can eat all tasty cookies, in the following order:

• A tasty cookie containing poison
• An untasty cookie containing antidotes
• A tasty cookie containing poison
• A tasty cookie containing antidotes
• A tasty cookie containing poison
• An untasty cookie containing antidotes
• A tasty cookie containing poison

### Sample Input 2

5 2 9


### Sample Output 2

10


### Sample Input 3

8 8 1


### Sample Output 3

9