[Dev-C++] string to array

[<his...@ya...>]

hi guys,
i am a newbie to dev as well as C++.
 
now i have to read a mathematical expression from the console as a string and then do some calcultions with it. 
how do i go about performing calculation.
the expression or eqn contains operators like +, -, / etc and also variables i.e alphabets like x,y etc.. in addition to numbers.
 
 is there some other to read the data rather than reading it into a string.
 
or can something be done so that numerical calculations can be made.
 
ex: read "2+3-x" should be able to output 5-x as the answer. 
 
please do help.
 
- sriram
 

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