题目描述
Problem Statement
Takahashi has a red jewel of level N. (He has no other jewels.)
Takahashi can do the following operations any number of times.
- Convert a red jewel of level n (n is at least 2) into "a red jewel of level (n-1) and X blue jewels of level n".
- Convert a blue jewel of level n (n is at least 2) into "a red jewel of level (n-1) and Y blue jewels of level (n-1)".
Takahashi wants as many blue jewels of level 1 as possible. At most, how many blue jewels of level 1 can he obtain by the operations?
Input
Input is given from Standard Input in the following format:
N X Y
Output
Print the answer.
Constraints
- $1 \leq N \leq 10$
- $1 \leq X \leq 5$
- $1 \leq Y \leq 5$
- All values in input are integers.
Sample Input 1
2 3 4
Sample Output 1
12
Takahashi can obtain 12 blue jewels of level 1 by the following conversions.
- First, he converts a red jewel of level 2 into a red jewel of level 1 and 3 blue jewels of level 2.
-
After this operation, Takahashi has 1 red jewel of level 1 and 3 blue jewels of level 2.
-
Next, he repeats the following conversion 3 times: converting a blue jewel of level 2 into a red jewel of level 1 and 4 blue jewels of level 1.
-
After these operations, Takahashi has 4 red jewels of level 1 and 12 blue jewels of level 1.
-
He cannot perform a conversion anymore.
He cannot obtain more than 12 blue jewels of level 1, so the answer is 12.
Sample Input 2
1 5 5
Sample Output 2
0
Takahashi may not be able to obtain a blue jewel of level 1.
Sample Input 3
10 5 5
Sample Output 3
3942349900
Note that the answer may not fit into a 32-bit integer type.
输入格式
见题面 Input 部分
输出格式
见题面 Output 部分