TRANSFORMATION

• Problem Description

  
  Reverse Polish Notation (RPN) is a mathematical notation where every operator follows all of its operands. For instance, to add three and four, one would write "3 4 +" rather than "3 + 4". If there are multiple operations, the operator is given immediately after its second operand; so the expression written "3 4 + 5" would be written "3 4 5 +" first subtract 4 from 3, then add 5 to that. 
  Transform the algebraic expression with brackets into RPN form. 
  You can assume that for the test cases below only single letters will be used, brackets [] will not be used and each expression has only one RPN form (no expressions like a*b*c) 
  Input
  The first line contains t, the number of test cases (less then 100). 
  Followed by t lines, containing an expression to be translated to RPN form, where the length of the expression is less then 400. 
  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+^*
  

• CODING ARENA

• #include <stdio.h>

  int main()

  {

    int cases,top=0,i;

    char exp[400],stack[200];

    scanf("%d",&cases);

    while(cases)

    {

      scanf("%s",exp);

      for(i=0;exp[i];i++)

      {

        if(exp[i]=='(')

          continue;

        else if(exp[i]==')')

        {

          printf("%c",stack[top]);

          top--;

        }

        else if(exp[i]=='+'|| exp[i]=='-'|| exp[i]=='*'|| exp[i]=='/'||exp[i]=='^')

        {

          top++;

          stack[top]=exp[i];

        }

        else

        {

          printf("%c",exp[i]);

        }

      }

      cases--;

      printf("\n");

    }

    return 0;

  }

                

                

  
  

• Test Case 1

  
  Input (stdin)

  3
  
  (a+(b*c))
  
  ((a+b)*(z+y))
  
  ((a+t)*((b+(a+c))^(c+d)))
  
  

  Expected Output

  abc*+
  
  ab+zy+*
  
  at+bac++cd+^*

• Test Case 2

  
  Input (stdin)

  2
  
  (a+(b*c))
  
  ((a+b)*(z+y))
  
  

  Expected Output

  abc*+
  
  ab+zy+*