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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 /content/datastructures/lichao.cpp
parentad3856a6b766087df0036de0b556f4700a6498c9 (diff)
parent8d11c6c8213f46f0fa19826917c255edd5d43cb1 (diff)
mzuenni tests
Diffstat (limited to 'content/datastructures/lichao.cpp')
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diff --git a/content/datastructures/lichao.cpp b/content/datastructures/lichao.cpp
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+vector<ll> xs; // IMPORTANT: Initialize before constructing!
+int findX(int i) {return lower_bound(all(xs), i) - begin(xs);}
+
+struct Fun { // Default: Linear function. Change as needed.
+ ll m, c;
+ ll operator()(int x) {return m*xs[x] + c;}
+};
+
+// Default: Computes min. Change lines with comment for max.
+struct Lichao {
+ static constexpr Fun id = {0, inf}; // {0, -inf}
+ int n, cap;
+ vector<Fun> seg;
+ Lichao() : n(sz(xs)), cap(2<<__lg(n)), seg(2*cap, id) {}
+
+ void _insert(Fun f, int l, int r, int i) {
+ while (i < 2*cap){
+ int m = (l+r)/2;
+ if (m >= n) {r = m; i = 2*i; continue;}
+ Fun &g = seg[i];
+ if (f(m) < g(m)) swap(f, g); // >
+ if (f(l) < g(l)) r = m, i = 2*i; // >
+ else l = m, i = 2*i+1;
+ }}
+ void insert(Fun f) {_insert(f, 0, cap, 1);}
+
+ void _segmentInsert(Fun f, int l, int r, int a, int b, int i) {
+ if (l <= a && b <= r) _insert(f, a, b, i);
+ else if (a < r && l < b){
+ int m = (a+b)/2;
+ _segmentInsert(f, l, r, a, m, 2*i);
+ _segmentInsert(f, l, r, m, b, 2*i+1);
+ }}
+ void segmentInsert(Fun f, ll l, ll r) {
+ _segmentInsert(f, findX(l), findX(r), 0, cap, 1);
+ }
+
+ ll _query(int x) {
+ ll ans = inf; // -inf
+ for (int i = x + cap; i > 0; i /= 2) {
+ ans = min(ans, seg[i](x)); // max
+ }
+ return ans;
+ }
+ ll query(ll x) {return _query(findX(x));}
+};