PROGRAMMING:Super staircase 2

###Problem Description
There's a super staircase. It's infinite. When you're on the ground at the beginning, you can step up the first level, or you can step up the second level.
Suppose you can only step up one or two levels at a time, then how many ways do you have to go up to level n?
###Input
The input data first contains a number of integers n (1 < = n < = 45), representing the number of stairs.
###Output
For each test case n, please output the number of steps to the nth stair.
###Sample Input
```in
two
five
eight
```
###Sample Output
```out
two
eight
thirty-four
```
###Sample Input
```in
forty-two
forty-three
forty-four
forty-five
```
###Sample Output
```out
four hundred and thirty-three million four hundred and ninety-four thousand four hundred and thirty-seven
seven hundred and one million four hundred and eight thousand seven hundred and thirty-three
one billion one hundred and thirty-four million nine hundred and three thousand one hundred and seventy
one billion eight hundred and thirty-six million three hundred and eleven thousand nine hundred and three
```






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