結果
問題 | No.913 木の燃やし方 |
ユーザー |
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提出日時 | 2019-10-19 11:31:57 |
言語 | C++17 (gcc 13.3.0 + boost 1.87.0) |
結果 |
AC
|
実行時間 | 1,000 ms / 3,000 ms |
コード長 | 6,318 bytes |
コンパイル時間 | 2,756 ms |
コンパイル使用メモリ | 202,280 KB |
最終ジャッジ日時 | 2025-01-07 23:59:49 |
ジャッジサーバーID (参考情報) |
judge1 / judge1 |
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ファイルパターン | 結果 |
---|---|
sample | AC * 3 |
other | AC * 34 |
コンパイルメッセージ
main.cpp: In member function ‘bool ConvexHullDynamic::Line::operator<(const ConvexHullDynamic::Line&) const’: main.cpp:50:17: warning: control reaches end of non-void function [-Wreturn-type] 50 | } | ^
ソースコード
#include<bits/stdc++.h>#define rep(i,a,b) for(int i=a;i<b;i++)#define rrep(i,a,b) for(int i=a;i>=b;i--)#define fore(i,a) for(auto &i:a)#define all(x) (x).begin(),(x).end()//#pragma GCC optimize ("-O3")using namespace std; void _main(); int main() { cin.tie(0); ios::sync_with_stdio(false); _main(); }typedef long long ll; const int inf = INT_MAX / 2; const ll infl = 1LL << 60;template<class T>bool chmax(T& a, const T& b) { if (a < b) { a = b; return 1; } return 0; }template<class T>bool chmin(T& a, const T& b) { if (b < a) { a = b; return 1; } return 0; }//---------------------------------------------------------------------------------------------------class ConvexHullDynamic{typedef long long coef_t;typedef long long coord_t;typedef long long val_t;/** Line 'y=a*x+b' represented by 2 coefficients 'a' and 'b'* and 'xLeft' which is intersection with previous line in hull(first line has -INF)*/private:struct Line{coef_t a, b;double xLeft;enum Type{line, maxQuery, minQuery} type;coord_t val;explicit Line(coef_t aa = 0, coef_t bb = 0) : a(aa), b(bb), xLeft(-INFINITY), type(Type::line), val(0) {}val_t valueAt(coord_t x) const { return a * x + b; }friend bool areParallel(const Line& l1, const Line& l2) { return l1.a == l2.a; }friend double intersectX(const Line& l1, const Line& l2) { return areParallel(l1, l2) ? INFINITY : 1.0 * (l2.b - l1.b) / (l1.a - l2.a); }bool operator<(const Line& l2) const{if (l2.type == line)return this->a < l2.a;if (l2.type == maxQuery)return this->xLeft < l2.val;if (l2.type == minQuery)return this->xLeft > l2.val;}};bool isMax; //whether or not saved envelope is top(search of max value)public:std::set< Line > hull; //envelope itselfprivate:/** INFO: Check position in hull by iterator* COMPLEXITY: O(1)*/bool hasPrev(std::set< Line >::iterator it) { return it != hull.begin(); }bool hasNext(std::set< Line >::iterator it) { return it != hull.end() && std::next(it) != hull.end(); }/** INFO: Check whether line l2 is irrelevant* NOTE: Following positioning in hull must be true* l1 is next left to l2* l2 is right between l1 and l3* l3 is next right to l2* COMPLEXITY: O(1)*/bool irrelevant(const Line& l1, const Line& l2, const Line& l3) { return intersectX(l1, l3) <= intersectX(l1, l2); }bool irrelevant(std::set< Line >::iterator it){return hasPrev(it) && hasNext(it)&& (isMax && irrelevant(*std::prev(it), *it, *std::next(it))|| !isMax && irrelevant(*std::next(it), *it, *std::prev(it)));}/** INFO: Updates 'xValue' of line pointed by iterator 'it'* COMPLEXITY: O(1)*/std::set< Line >::iterator updateLeftBorder(std::set< Line >::iterator it){if (isMax && !hasPrev(it) || !isMax && !hasNext(it))return it;double val = intersectX(*it, isMax ? *std::prev(it) : *std::next(it));Line buf(*it);it = hull.erase(it);buf.xLeft = val;it = hull.insert(it, buf);return it;}public:explicit ConvexHullDynamic(bool isMax = false) : isMax(isMax) {}/** INFO: Adding line to the envelope* Line is of type 'y=a*x+b' represented by 2 coefficients 'a' and 'b'* COMPLEXITY: Adding N lines(N calls of function) takes O(N*log N) time*/void addLine(coef_t a, coef_t b){//find the place where line will be inserted in setLine l3 = Line(a, b);auto it = hull.lower_bound(l3);//if parallel line is already in set, one of them becomes irrelevantif (it != hull.end() && areParallel(*it, l3)) {if (isMax && it->b < b || !isMax && it->b > b)it = hull.erase(it);elsereturn;}//try to insertit = hull.insert(it, l3);if (irrelevant(it)) {hull.erase(it);return;}//remove lines which became irrelevant after inserting linewhile (hasPrev(it) && irrelevant(std::prev(it))) hull.erase(std::prev(it));while (hasNext(it) && irrelevant(std::next(it))) hull.erase(std::next(it));//refresh 'xLine'it = updateLeftBorder(it);if (hasPrev(it))updateLeftBorder(std::prev(it));if (hasNext(it))updateLeftBorder(std::next(it));}val_t getBest(coord_t x) const{Line q;q.val = x;q.type = isMax ? Line::Type::maxQuery : Line::Type::minQuery;auto bestLine = hull.lower_bound(q);if (isMax) --bestLine;return bestLine->valueAt(x);}};/*---------------------------------------------------------------------------------------------------∧_∧∧_∧ (´<_` ) Welcome to My Coding Space!( ´_ゝ`) / ⌒i @hamayanhamayan/ \ | |/ / ̄ ̄ ̄ ̄/ |__(__ニつ/ _/ .| .|____\/____/ (u ⊃---------------------------------------------------------------------------------------------------*/int N, A[201010];ll B[201010];//---------------------------------------------------------------------------------------------------void f(int L, int R, vector<ll>& ans, bool isRev = false) {if (L + 1 == R) {chmin(ans[L], 1LL + A[L]);return;}int md = (L + R) / 2;if (isRev and (R - L) % 2 == 1) md++;f(L, md, ans, isRev);f(md, R, ans, isRev);ConvexHullDynamic cht;rep(i, md, R) cht.addLine(-2LL * (i + 1), 1LL * (i + 1) * (i + 1) + B[i]);ll mi = infl;rep(i, L, md) {ll cst = cht.getBest(i) + 1LL * i * i;if (i) cst -= B[i - 1];chmin(mi, cst);chmin(ans[i], mi);}}//---------------------------------------------------------------------------------------------------void _main() {cin >> N;rep(i, 0, N) cin >> A[i];vector<ll> normal(N, infl);B[0] = A[0];rep(i, 1, N) B[i] = B[i - 1] + A[i];f(0, N, normal);reverse(A, A + N);vector<ll> rev(N, infl);B[0] = A[0];rep(i, 1, N) B[i] = B[i - 1] + A[i];f(0, N, rev, true);rep(i, 0, N) printf("%lld\n", min(normal[i], rev[N - 1 - i]));}