PROGRAMMING:Crawling worms
A worm is one inch long, at the bottom of an n-inch-deep well. It is known that worms can climb up u-inch every minute, but they have to rest for one minute before they can climb up. In the process of rest, the worm slipped D inch. In this way, climbing and sliding are repeated. How long does it take for the worm to climb out of the well?
It is assumed that as long as the head of the worm reaches the top of the well in a certain climbing process, the worm will complete the task. Initially, the worm is lying at the bottom of the well (i.e. the height is 0).
###Input format:
Input three positive integers n, u, D in one line, where d $$< $$u, n does not exceed 100.
###Output format:
Output the time in minutes for the worm to climb out of the well in a row.
###Input example:
```in
12 3 1
```
###Output example:
```out
eleven
```
answer：If there is no answer, please comment
It is assumed that as long as the head of the worm reaches the top of the well in a certain climbing process, the worm will complete the task. Initially, the worm is lying at the bottom of the well (i.e. the height is 0).
###Input format:
Input three positive integers n, u, D in one line, where d $$< $$u, n does not exceed 100.
###Output format:
Output the time in minutes for the worm to climb out of the well in a row.
###Input example:
```in
12 3 1
```
###Output example:
```out
eleven
```
answer：If there is no answer, please comment