PROGRAMMING:Apple tray

There are n apples to be loaded on a plate, two for each plate. Program to input the number of apples N and output how many plates these apples can be loaded on.
###Input format:
An integer n.
###Output format:
An integer, the number of plates.
#####Input example:
```in
fifteen
```
#####Output example:
```out
eight
```
#####Input example:
```in
twenty
```
#####Output example:
```out
ten
```







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