Contest Duration: - (local time) (110 minutes) Back to Home
A - Divide a Cuboid /

Time Limit: 2 sec / Memory Limit: 256 MB

### 問題文

1×1×1 のブロックが A×B×C の直方体状に並んでいます。 高橋君は各ブロックを赤色または青色で塗ろうとしています。 このとき、次の条件が成り立つようにします。

• 赤いブロックも青いブロックもそれぞれ 1 個以上ある。
• 赤いブロック全体が 1 つの直方体状になっている。
• 青いブロック全体が 1 つの直方体状になっている。

• 2≤A，B，C≤10^9

### 入力

A B C


### 入力例 1

3 3 3


### 出力例 1

9


### 入力例 2

2 2 4


### 出力例 2

0


### 入力例 3

5 3 5


### 出力例 3

15


Score : 200 points

### Problem Statement

We have a rectangular parallelepiped of size A×B×C, built with blocks of size 1×1×1. Snuke will paint each of the A×B×C blocks either red or blue, so that:

• There is at least one red block and at least one blue block.
• The union of all red blocks forms a rectangular parallelepiped.
• The union of all blue blocks forms a rectangular parallelepiped.

Snuke wants to minimize the difference between the number of red blocks and the number of blue blocks. Find the minimum possible difference.

• 2≤A,B,C≤10^9

### Input

The input is given from Standard Input in the following format:

A B C


### Output

Print the minimum possible difference between the number of red blocks and the number of blue blocks.

### Sample Input 1

3 3 3


### Sample Output 1

9


For example, Snuke can paint the blocks as shown in the diagram below. There are 9 red blocks and 18 blue blocks, thus the difference is 9.

### Sample Input 2

2 2 4


### Sample Output 2

0


For example, Snuke can paint the blocks as shown in the diagram below. There are 8 red blocks and 8 blue blocks, thus the difference is 0.

### Sample Input 3

5 3 5


### Sample Output 3

15


For example, Snuke can paint the blocks as shown in the diagram below. There are 45 red blocks and 30 blue blocks, thus the difference is 9.