PROGRAMMING:Mathematical Operations

### Input Format:
The first line is a number The second line is an operator (+,-,*,/) The last line is a number
### Output Format:
Output the result of an operation(2 decimal places)
If the divisor is zero, the error 'divided by zero' is displayed.
### Sample Inputs1:
```in
seven
/
three
```
### Sample Output1:
```out
two point three three
```
### Sample Inputs2:
```in
ten
/
0
```
### Sample Output2:
```out
divided by zero
```






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