"((3+5)*4)-(40/2)-10)" =????

[Phogang]

When user enter any string on EditBox like... "((3+5)*4)-(40/2)-10)".
how to make my program give the numerical result from the string.

[alexey_1979]

There are many tools and libs for math operations. Search the site, plz.

[Ejaz]

Dear Phogang,

to do mathematical tasks like that, u'll have to use data structures, by using 2 stacks, the desired operations can be achieved, for that in one stack u'll put the operands and in other the operators.

suppose the expration is 2 + 1 , then

parsing from left, first u get 2, put it in one stack, then u get an
operator (+ here), u put it in the other stack, now again u get another operand (1), since the experation has ended, pop last operand, store it in a variable, then pop operator (+), agian pop oprand ( 2 ) and then perform the addition.

The main point is never override the perorities of opertors( like * or / )can't be put below lower precidence operators (like +,-), if any situation arises, then first perform the steps mentioned above, get their result, and store that result in the operand stack.

if u encounter ( ), then store ( in operators stack, when u receive ), again start poping till u get ( in operators stack, perfrom arithematics and store the result in the operands stack.

I'll try to arrange the code for u, since I don't have it right now.

Hope this will give u some idea, for further details, u can consult
any nice book of data structures using C/C++ in stacks session.

Regards,

Ejaz.

[vovkin]

i have this program code, but it wrote in Delphi
if you want, i may write it here

[vovkin]

wow, i found thiscode on c++
write your email and i send it in *.rar format

[Phogang]

my email address is phogang@hotmail.com

thank you very much for your sourcecode (zip format is best, my machine do not have winrar)

thank you.

[vovkin]

i sent from e-mail vovkin@kernel.lv