PROGRAMMING:Calculation expression (*, / /,%)

Enter an expression in the form of "operands operator operands" to multiply, divide and remainder two integers (%).
###Input format:
On one line, enter an expression in the form of an operatoroperatoroperatoroperatoroperatoroperatoroperatoroperatoroperatoroperatoroperatoroperatoroperatoroperatoroperatoroperatoroperatoroperatoroperatoroperatoroperatoroperatoroperatoroperatoroperatoroperatoroperatoroperatoropera.
###Output format:
Output the expression and calculation result in one line.
###Input sample 1:
Here is a set of inputs. For example:
```in
21 * 8
```
###Output sample 1:
The corresponding output is given here. For example:
```out
21*8=168
```
###Input sample 2:
Here is a set of inputs. For example:
```in
21 ! eight
```
###Output sample 1:
The corresponding output is given here. For example:
```out
Invalid operator
```







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