ONP  Transform the Expression
Transform the algebraic expression with brackets into RPN form (Reverse Polish Notation). Twoargument operators: +, , *, /, ^ (priority from the lowest to the highest), brackets ( ). Operands: only letters: a,b,...,z. Assume that there is only one RPN form (no expressions like a*b*c).
Input
t [the number of expressions <= 100] expression [length <= 400] [other expressions]
Text grouped in [ ] does not appear in the input file.
Output
The expressions in RPN form, one per line.
Example
Input: 3 (a+(b*c)) ((a+b)*(z+x)) ((a+t)*((b+(a+c))^(c+d))) Output: abc*+ ab+zx+* at+bac++cd+^*
Added by:  Michał Małafiejski 
Date:  20040501 
Time limit:  5s 
Source limit:  50000B 
Memory limit:  1536MB 
Cluster:  Cube (Intel Pentium G860 3GHz) 
Languages:  All except: NODEJS PERL 6 VB.net 
Resource:   
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Amritendu Mondal:
20150810 11:17:21
I didn't use stack but a tree to store the expression. Good problem , happy to solve this type. 

gaurav:
20150808 09:48:11
Are there any boundary conditions we need to check for?


MishThi:
20150805 11:46:31
Taught me about how stacks function. A great problem for beginners to learn about Stacks. Also, my 49th. :D 

c_lauw97:
20150801 07:18:47
if the input was (a+b^c) , the output should be abc^+ ? true or not? need explanation for several test case 

sudomudo:
20150719 23:45:01
Use stack, and don't forget to format the output the right way. GG :) 

treyshaffer:
20150719 00:37:02
A good algorithm for solving this problem:


seamel_1:
20150716 16:18:53
Could someone tell me what is wrong in my code http://pastebin.com/fG8x8QTC compile and works well but spoj detects runtime error (SIGSEGV) 

Supreme:
20150714 13:52:23
Tried solving without using stacks  didnt get the solution even after 2 days.


himanshu kumar:
20150713 18:25:28
please do see the priority hehe... giving me one wrong answer :p 

artista_14:
20150628 15:09:30
STL made code shorter......Excellent problem for beginners....... 