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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/segmentTree.cpp
parentad3856a6b766087df0036de0b556f4700a6498c9 (diff)
parent8d11c6c8213f46f0fa19826917c255edd5d43cb1 (diff)
mzuenni tests
Diffstat (limited to 'datastructures/segmentTree.cpp')
-rw-r--r--datastructures/segmentTree.cpp43
1 files changed, 0 insertions, 43 deletions
diff --git a/datastructures/segmentTree.cpp b/datastructures/segmentTree.cpp
deleted file mode 100644
index 1fbf886..0000000
--- a/datastructures/segmentTree.cpp
+++ /dev/null
@@ -1,43 +0,0 @@
-struct SegTree {
- using T = ll;
- int n;
- vector<T> tree;
- static constexpr T E = 0; // Neutral element for combine
-
- SegTree(vector<T>& a) : n(ssize(a)), tree(2 * n, E) {
- ranges::copy(a, tree.begin() + n);
- //SegTree(int size, T val = E) : n(size), tree(2 * n, E) {
- // fill(tree.begin() + n, tree.end(), val);
- for (int i = n - 1; i > 0; i--) { // remove for range update
- tree[i] = comb(tree[2 * i], tree[2 * i + 1]);
- }}
-
- T comb(T a, T b) { return a + b; } // modify this + neutral
-
- void update(int i, T val) {
- tree[i += n] = val; // apply update code
- while (i /= 2) tree[i] = comb(tree[2 * i], tree[2 * i + 1]);
- }
-
- T query(int l, int r) {
- T resL = E, resR = E;
- for (l += n, r += n; l < r; l /= 2, r /= 2) {
- if (l&1) resL = comb(resL, tree[l++]);
- if (r&1) resR = comb(tree[--r], resR);
- }
- return comb(resL, resR);
- }
-
- // OR: range update + point query, needs commutative comb
- void modify(int l, int r, T val) {
- for (l += n, r += n; l < r; l /= 2, r /= 2) {
- if (l&1) tree[l] = comb(tree[l], val), l++;
- if (r&1) --r, tree[r] = comb(tree[r], val);
- }}
-
- T query(int i) {
- T res = E;
- for (i += n; i > 0; i /= 2) res = comb(res, tree[i]);
- return res;
- }
-};