I need a help to solve algorithm problem!

Suppose that we are to search a list of 700 million items using the Recursive Binary Search algorithm. What is the maximum number of comparisons that this algorithm must perform (i.e. the worst case) before finding a given item or concluding that it is not in the list? Please show how you arrived at your solution.

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Recursive Binary Search Algorithm

Problem - Determine whether x is in the sorted array S of size n.

Inputs - positive integer n, sorted (nondecreasing order) array of keys S indexed from 1 to n, a key x.

Outputs - location, the location of x in S (0 if x is not is S).

index location (index low, index high)

{

index mid;

if (low>high)

return 0;

else {

mid = [(low + high)/2];

return mid

else if (x < S[mid])

return location (low, mid -1);

else

return location (mid + 1. high);

}

}

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