Question

Q2:

The following code is supposed to return the sum of the numbers between 1 and n inclusive, for positive n. An analysis of the code using our "Three Question" approach reveals that:

int sum(int n){

if (n == 1)

    return 1;

else

    return (n + sum(n - 1));

}

Answer Choices:

it passes on all three questions and is a valid algorithm.

   

it fails the smaller-caller question.

   

it fails the base-case question.

   

it fails the general-case question.

Q3:

What does the following return, when passed the argument 1564?

int recur(int n)

{

if (n < 0) return -1;

else

    if (n < 10) return n;

    else

      return ((n % 10) + recur(n / 10));

}

Answer Choices:

160

   

16

   

-1

   

4

Q4:

The following code is supposed to return n!, for positive n. An analysis of the code using our "Three Question" approach reveals that:

int factorial(int n){

if (n == 0)

    return 2;

else

    return (n * factorial(n – 1));

}

Answer Choices:

it fails the base-case question.

   

it fails the general-case question.

   

it passes on all three questions and is a valid algorithm.

   

it fails the smaller-caller question.

Answer 1

Q2.

Ans: (a) it passes on all three questions and is a valid algorithm.

Because it satisfies all case.

Q3.

Ans: 16

It adds all the digits of the number.

Q4.

Ans: (a)  it fails the base-case question.

Here base case is 0!=1 and 1!=1

But these condtions are not correct in program . so base case fails.

Here base case fails . so entire program is wrong it does not satisfy any case.