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rahulraina7 - n00b
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Any body has a solution to this code..!!
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by rahulraina7 » Wed Sep 05, 2012 5:40 am
I am not asking any 1 to write it , but preferably looking for a person who already has the solution for this code..!!!
Preferable language is c/c++ .
Code: Select all
An expression consisting of operands and binary operators can be written in Reverse Polish Notation (RPN) by writing both the operands followed by the operator. For example, 3 + (4 * 5) can be written as "3 4 5 * +".
You are given a string consisting of x's and *'s. x represents an operand and * represents a binary operator. It is easy to see that not all such strings represent valid RPN expressions. For example, the "x*x" is not a valid RPN expression, while "xx*" and "xxx**" are valid expressions. What is the minimum number of insert, delete and replace operations needed to convert the given string into a valid RPN expression?
Input:
The first line contains the number of test cases T. T test cases follow. Each case contains a string consisting only of characters x and *.
Output:
Output T lines, one for each test case containing the least number of operations needed.
Constraints:
1 <= T <= 100
The length of the input string will be at most 100.
Sample Input:
5
x
xx*
xxx**
*xx
xx*xx**
Sample Output:
0
0
0
2
0
Explanation:
For the first three cases, the input expression is already a valid RPN, so the answer is 0.
For the fourth case, we can perform one delete, and one insert operation: *xx -> xx -> xx*
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Cool_Fire
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by Cool_Fire » Wed Sep 05, 2012 6:50 pm
This is know as postfix notation. The only thing you need to do is push everything onto a stack until you hit an operator, pop the two operands and push the result back onto the stack.
Post Reply [phpBB Debug] PHP Warning: in file
[ROOT]/vendor/twig/twig/lib/Twig/Extension/Core.php on line
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count(): Parameter must be an array or an object that implements Countable
[phpBB Debug] PHP Warning: in file
[ROOT]/vendor/twig/twig/lib/Twig/Extension/Core.php on line
1275:
count(): Parameter must be an array or an object that implements Countable