- Choose one of the operators AND (&), OR (|) or XOR (^). Suppose the current string is S = s1s2...sk. Then, for all. , replace s2i-1s2i with the result obtained by applying the operator to s2i-1 and s2i. For example, if we apply XOR to {1101} we get {01}.After n operations, the string will have length 1.There are 3n ways to choose the n operations in total. How many of these ways will give 1 as the only character of the final string.
A binary string s of length N = 2n is given. You will perform the following operation n times : - Choose one of the operators AND (&), OR (|) or XOR (^). Suppose the current string is S = s1s2...sk. Then, for all 1 le i le frac{k}{2} 1≤i≤ 2 k , replace s2i-1s2i with the result obtained by applying the operator to s2i-1 and s2i. For example, if we apply XOR to {1101} we get {01}. After n operations, the string will have length 1. There are 3n ways to choose the n operations in total. How many of these ways will give 1 as the only character of the final string.
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