**Problem Description**

**Input**

There will be multiple problem instances. Each line will contain 3 positive integers n, u and d. These give the values mentioned in the paragraph above. Furthermore, you may assume d < u and n < 100. A value of n = 0 indicates end of output.

**Output**

Each input instance should generate a single integer on a line, indicating the number of minutes it takes for the worm to climb out of the well.

**Sample Input**

10 2 1 20 3 1 0 0 0

**Sample Output**

17 19

**Source**

East Central North America 2002，Practice