在解决刺伤问题时,在哪里可以找到实现分段树的参考?刺伤问题要求返回包含给定点 q 的所有间隔(从 [a, b], 1 <= a <= b <= n 形式为 [a, b], 1 <= a <= b <= n 的预定义的一组 m 间隔)返回。
极端情况:只有一点 [a, a] 的区间。
到目前为止,我设法获得了以下代码,但它肯定不起作用,我无法真正找到错误:
int n, m, x[100005], y[100005], q;
list< int > segm[200005];
//Search for q in the segment tree
void segmQuery(int node, int left, int right)
{
for (list<int>::iterator i = segm[node].begin(); i != segm[node].end(); i++)
{
//Process the segment
}
if (left < right)
{
int middle = left + (right - left) / 2;
if (q <= middle)
segmQuery(2 * node, left, middle);
if (q > middle)
segmQuery(2 * node + 1, middle + 1, right);
}
}
//Add the q-th segment into the tree
//Segment is denoted by x[q], y[q]
void segmAdd(int node, int left, int right)
{
if ((x[q] <= left) && (right <= y[q]))
segm[node].push_back(q);
else
{
int middle = left + (right - left) / 2;
if (x[q] <= middle)
segmAdd(2 * node, left, middle);
if (y[q] > middle)
segmAdd(2 * node + 1, middle + 1, right);
}
}