summaryrefslogtreecommitdiff
path: root/datastructures/waveletTree.cpp
diff options
context:
space:
mode:
authorGloria Mundi <gloria@gloria-mundi.eu>2024-11-16 01:24:14 +0100
committerGloria Mundi <gloria@gloria-mundi.eu>2024-11-16 01:24:14 +0100
commit98567ec798aa8ca2cfbcb85c774dd470f30e30d4 (patch)
tree5113d5cc24d1ad5f93810b6442ce584a36950dc8 /datastructures/waveletTree.cpp
parentad3856a6b766087df0036de0b556f4700a6498c9 (diff)
parent8d11c6c8213f46f0fa19826917c255edd5d43cb1 (diff)
mzuenni tests
Diffstat (limited to 'datastructures/waveletTree.cpp')
-rw-r--r--datastructures/waveletTree.cpp32
1 files changed, 0 insertions, 32 deletions
diff --git a/datastructures/waveletTree.cpp b/datastructures/waveletTree.cpp
deleted file mode 100644
index 95ff207..0000000
--- a/datastructures/waveletTree.cpp
+++ /dev/null
@@ -1,32 +0,0 @@
-struct WaveletTree {
- unique_ptr<WaveletTree> ln, rn;
- vector<int> b = {0};
- ll lo, hi;
-
- WaveletTree(auto in) : lo(*ranges::min_element(in)),
- hi(*ranges::max_element(in) + 1) {
- ll mid = (lo + hi) / 2;
- auto f = [&](ll x) { return x < mid; };
- for (ll x: in) b.push_back(b.back() + f(x));
- if (lo + 1 >= hi) return;
- auto right = ranges::stable_partition(in, f);
- ln = make_unique<WaveletTree>(
- ranges::subrange(begin(in), begin(right)));
- rn = make_unique<WaveletTree>(right);
- }
-
- ll kth(int l, int r, int k) {
- if (l >= r || k >= r - l) return -1;
- if (lo + 1 >= hi) return lo;
- int inLeft = b[r] - b[l];
- if (k < inLeft) return ln->kth(b[l], b[r], k);
- else return rn->kth(l-b[l], r-b[r], k-inLeft);
- }
-
- int countSmaller(int l, int r, ll k) {
- if (l >= r || k <= lo) return 0;
- if (hi <= k) return r - l;
- return ln->countSmaller(b[l], b[r], k) +
- rn->countSmaller(l-b[l], r-b[r], k);
- }
-};