Hello,

I've copied this from the Beginners forum, as I malignantly

posted it there originally.

I am trying to pass a

string that represents a postfix expression. The method that accepts it should take each number and place it on the stack. When it encounters an operator, it should pop the top two numbers and evaluate them with the operator.

This is the expression. "abc+-"

a=7, b=3, c=12 So it applies "+" to c and b, then it subtracts (c + b) from a. I have made the string into a string array in my program, but I think the idea is to pass the expression as a regular string as I have it above. I would use substring(), but that doesn't work with a number larger than 2 digits. Thanks!