Consider the following definition of the recursive function mystery. int mystery(int first,int last)
{
if (first > last)
$\quad$ Return 0;
else if (first == last)
$\quad$ Return first;
else
$\quad$ return first + mystery(first + 1,last - 1) ;
}
What is the output of the following statement?
cout << mystery(6,10) << endl;

Question

Consider the following definition of the recursive function mystery. int mystery(int first,int last)
{
if (first > last)
$\quad$Return 0;
else if (first == last)
$\quad$Return first;
else
$\quad$return first + mystery(first + 1,last - 1);
}
What is the output of the following statement?
cout << mystery(6,10)<< endl;
A) 13
B) 21
C) 40
D) 42

Quizplus · Accepted Answer

The function sums the numbers from 'first' to 'last' by recursively calling itself with incremented 'first' and decremented 'last'. For mystery(6,10), it calculates 6 + 7 + 8 = 21.

Consider the Following Definition of the Recursive Function Mystery \quad Return 0; Else If (First == Last)

Consider the Following Definition of the Recursive Function Mystery $\quad$ Return 0;
Else If (First == Last)