READYBIT APRIL LONG CHALLENGE

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Guys,how did u solve the readybit question?

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Wait for the editorial.

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Let P_e(x) be the probability that an expression e evaluates to x where x \in \{0,1,a,A\}

If e is “#”, P_e(x) = \frac{1}{4} forall \ x \in \{0,1,a,A\}.

You can recursively calculate P_e(x) for any e which is of the form e_1\ o \ e_2 where o is an operator and e_1,e_2 are expressions using the following pseudocode:

for x in {0,1,a,A}
    P_e(x) = 0
for x1 in {0,1,a,A}
    for x2 in {0,1,a,A}
        P_e(x o y) += P_e1(x)*P_e2(y)
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We are given with infix expression. You should change it to postfix or prefix expression which will make you solve problem more easily.
Here is my source code: CodeChef: Practical coding for everyone
Above link is showing access denied due to some error, you can check code at Online Compiler and IDE >> C/C++, Java, PHP, Python, Perl and 70+ other compilers and interpreters - Ideone.com

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It’s showing access denied,bro!

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Check from here Online Compiler and IDE >> C/C++, Java, PHP, Python, Perl and 70+ other compilers and interpreters - Ideone.com

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You can assume or transform \{0, a, A, 1\} \to \{0, 1, 2, 3\}, then the operations have their respective meanings on this set.
Now calculate the probablities recursively. Let left and right expressions have probabilties P_l and P_r, to calculate it for the new expression P(x) = \sum\limits_{u \circ v = x}{P_l(u)P_r(v)}

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