What is wrong with the following recursive sum method? The method is supposed to sum up the values between 1 and x (for instance, sum(5) should be 5 + 4 + 3 + 2 + 1 = 15).
Public int sum(int x)
{
If (x = = 0) return 0;
Else return sum(x - 1) + x;
}
A) the base case should return 1 instead of 0
B) the recursive case should return sum(x - 1) + 1; instead of sum(x - 1) + x;
C) the base case condition should be (x

Question

What is wrong with the following recursive sum method? The method is supposed to sum up the values between 1 and x (for instance, sum(5) should be 5 + 4 + 3 + 2 + 1 = 15).
Public int sum(int x)
{
If (x = = 0) return 0;
Else return sum(x - 1) + x;
}
A) the base case should return 1 instead of 0
B) the recursive case should return sum(x - 1) + 1; instead of sum(x - 1) + x;
C) the base case condition should be (x <= 0) instead of (x = = 0)
D) the recursive case should return sum(x) + 1;
E) the method should return a boolean instead of an int

Quizplus · Accepted Answer

C) The method does not appropriately handle a negative parameter, such as sum(-5). The result is infinite recursion. We might define a negative parameter as something that should return 0, or allow a negative parameter to compute a negative sum as in:
public int sum(int x)
{
if (x = = 0) return 0;
else if (x < 0) return -1 * sum(-x);
else return sum(x - 1) + x;
}

What Is Wrong with the Following Recursive Sum Method? the Method