PROGRAMMING:Calculation of natural gas

The gradient charging system is adopted for natural gas in a residential area. When a household uses less than 10 cubic meters of natural gas (including 10 cubic meters), it will charge 2 yuan per cubic meter of natural gas; When users use more than 10 cubic meters of natural gas, the cost of the excess is 3 yuan per cubic meter.
###Input format:
Enter an integer greater than or equal to 0 and less than or equal to 100
###Output format:
Cost of direct export of natural gas
###Input example:
Here is a set of inputs. For example:
```in
ten
```
###Output example:
The corresponding output is given here. For example:
```out
twenty
```
###Input example:
Here is a set of inputs. For example:
```in
nine
```
###Output example:
The corresponding output is given here. For example:
```out
eighteen
```
###Input example:
Here is a set of inputs. For example:
```in
eleven
```
###Output example:
The corresponding output is given here. For example:
```out
twenty-three
```







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