Virtual Labs

Recursion

1. How many stars will the following code output for a given positive value of n:

a: n Explanation

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b: n^2 Explanation

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c: n(n-1)/2 Explanation

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d: n(n+1)/2 Explanation

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2. What will be the ouptut of the following function call: fun2(20); where fun2 is defined as:

a: 20 40 60 80 60 40 20 Explanation

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b: 80 60 40 20 Explanation

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c: 20 40 60 80 80 60 40 20 Explanation

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d: 20 40 60 80 Explanation

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3. What will be the ouptut of the following function call: fun3(100); where fun3 is defined as:

a: 6 Explanation

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b: 7 Explanation

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c: 5 Explanation

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d: 4 Explanation

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4. In Python, which module or library allows you to control the maximum recursion depth?

a: recursioncontrol Explanation

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b: sys Explanation

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c: recursivelimit Explanation

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d: recursivecontrol Explanation

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5. What is the time complexity of the following recursive function for computing Fibonacci numbers?

a: O(n) Explanation

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b: O(log n) Explanation

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c: O(2^n) Explanation

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d: O(n^2) Explanation

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6. How does the compiler or interpreter handle tail recursion?

a: By converting it into a loop Explanation

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b: By using a special optimization technique Explanation

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c: By adding a flag to indicate tail recursion Explanation

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d: By doing nothing, tail recursion works as usual Explanation

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7. Can recursion be used to solve parallel computing problems?

a: Yes, recursion can be used to solve parallel computing problems Explanation

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b: No, recursion is not useful for parallel computing Explanation

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c: Sometimes, depending on the specific problem Explanation

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d: Only if the problem has a small number of inputs Explanation

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8. Which of the following is a valid way to write a recursive function for calculating the Fibonacci sequence?

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d: None of the above Explanation

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9. Consider the following recursive function fun(x, y). What is the value of fun(4, 3)?

a: 9 Explanation

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b: 10 Explanation

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c: 11 Explanation

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d: 12 Explanation

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e: 13 Explanation

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10. What does the following function print for n = 25?

a: 11001 Explanation

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b: 10011 Explanation

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c: 11111 Explanation

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d: 00000 Explanation

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e: None of the above Explanation

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11. What does the following function do?

a: x + y Explanation

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b: x + x*y Explanation

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c: x*y Explanation

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d: x^y Explanation

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e: None of the above Explanation

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12. What does fun2() do in general?

a: x*y Explanation

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b: x + x*y Explanation

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c: y^x Explanation

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d: x^y Explanation

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e: None of the above Explanation

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13. Consider the recursive C++ function that takes two arguments.

What is the return value of the function foo when it is called as foo(513, 2)?

a: 2 Explanation

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b: 5 Explanation

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c: 8 Explanation

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d: 9 Explanation

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e: None of the above Explanation

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