PROGRAMMING:Xiao Ming moves bricks

One day, Xiao Ming went to the brick yard to experience life, and a pile of n (0 < n < = 40) bricks needed to be moved from the construction site to the car. Xiao Ming thought, if you move one or two bricks at a time, how many possible ways to move n bricks? Please help Xiao Ming calculate.
###Input format:
Enter n bricks.
###Output format:
The number of ways to move bricks.
###Input example:
```in
one
```
###Output example:
```out
one
```
###Input example:
```in
forty-five
```
###Output example:
```out
error!
```






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