单选题：算法分析(应用)

算法分析(应用)

下面 SumPower 函数的时间复杂度为 ▁▁▁▁▁ 。@[D](1)

```c
double Power(double x, int n)
{
double y = 1.0, p = x;
int t = n;
for (t = n; t > 0; t /= 2)
{
if (t % 2)
{
y *= p;
}
p *= p;
}
return y;
}

double SumPower(double x, int n)
{
double y = 0.0;
int k;
for (k = 1; k <= n; ++k)
{
y += Power(x, n);
}
return y;
}
```

A. $$O(n ^ 2)$$
B. $$O(2 ^ n)$$
C. $$O(\log _ 2 n)$$
D. $$O(n \log _ 2 n)$$
E. $$O(n)$$
F. $$O(1)$$
G. $$O(\sqrt n)$$
H. $$O(n \sqrt n)$$




A.$$O(n ^ 2)$$
B.$$O(2 ^ n)$$
C.$$O(\log _ 2 n)$$
D.$$O(n \log _ 2 n)$$
E.$$O(n)$$
F.$$O(1)$$
G.$$O(\sqrt n)$$
H.$$O(n \sqrt n)$$


答案：D