Problem
Write a Java program that calculates the result of a postfix arithmetic expression. 5*(((11-3)/4)-1)
The data is separated by spaces. The program uses a stack to save the numeric values once they are read. Once an operator is read the program unstacks the last two values in the stack, performs the operation, then pushes the result. The end result is the contents of the stack after all elements are processed. Accepted operations are -,+, *, /.