i'm learning about JAVA language but this one is very difficult, so please help me if you guys can. Create a simple calculator program.

The program will receive a String input which begin with a number and finish/end with an equation mark/character: = Assume that user will always give a correct input Reject input that do not begin with number and ending with = The program need to have these behavior: Can not have bracket ( ) Do not follow hierarchy order of calculation, calculation will always start from left to right, regardless of the operation type.

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Example:

Input: 1+2-3*4/5=

Output: 0

Input: 2+4/3

Output: Exception(error)

Example:

Input: (2+3)+4

Output: Exception(error)

Input: 2+4/3=

Output: 2

Input: 2+-5+4=

Output: Exception(error)