Submission #251307

#	Time	Username	Problem	Language	Result	Execution time	Memory
251307		Haunted_Cpp	Building Bridges (CEOI17_building)	C++17	0 / 100	271 ms	131072 KiB

building

/**
 *  author: Haunted_Cpp
**/
 
#include <bits/stdc++.h>
using namespace std;
 
#pragma GCC optimize("Ofast")
#pragma GCC target("fma,sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,avx2,tune=native")
#pragma GCC optimize("unroll-loops")
 
template<typename T> ostream &operator << (ostream &os, const vector<T> &v) { os << '{'; string sep; for (const auto &x : v) os << sep << x, sep = ", "; return os << '}'; }
template<typename T, size_t size> ostream &operator << (ostream &os, const array<T, size> &arr) { os << '{'; string sep; for (const auto &x : arr) os << sep << x, sep = ", "; return os << '}'; }
template<typename A, typename B> ostream &operator << (ostream &os, const pair<A, B> &p) { return os << '(' << p.first << ", " << p.second << ')'; }
 
void debug_out() { cerr << endl; }
template<typename Head, typename... Tail> void debug_out(Head H, Tail... T) { cerr << ' ' << H; debug_out(T...); }
 
#ifdef LOCAL
#define debug(...) cerr << "(" << #__VA_ARGS__ << "):", debug_out(__VA_ARGS__)
#else
#define debug(...) 47
#endif
 
typedef long long i64;
typedef pair<i64, i64> pi64;
 
const i64 INF = 1e18;
const int MAX_N = 2e6 + 5;
 
i64 dp[MAX_N], h[MAX_N], c[MAX_N];
 
i64 f(pi64 linha, int x) {
	return linha.first * x + linha.second;
}
 
struct LiChao {
	const int L;
	vector<pi64> seg;
	LiChao(int n) : L(n + 5) {
		seg.clear();
		seg = vector<pi64>(4 * L, {0, INF});
	}
	void add(pi64 linha, int l, int r, int node) {
		int mid = l + (r - l) / 2;
		bool left = f(linha, l) < f(seg[node], l);
		bool middle = f(linha, mid) < f(seg[node], mid); 
		if (middle) {
			swap(seg[node], linha);
		}
		if (r == l) {
			return;
		} else if (left != middle) {
			add(linha, l, mid, 2 * node + 1);
		} else {
			add(linha, mid + 1, r, 2 * node + 2);
		}	
	}
	i64 get(int l, int r, int where, int node) {
		int mid = l + (r - l) / 2;
		if (r == l) {
			return f(seg[node], where);
		} else if (where < mid) {
			return min(f(seg[node], where), get(l, mid, where, 2 * node + 1));
		} else {
			return min(f(seg[node], where), get(mid + 1, r, where, 2 * node + 2));
		}
	}
};
 
int main () {
  ios::sync_with_stdio(0);
  cin.tie(0);
  int n;
  cin >> n;
  for (int i = 0; i < n; i++) cin >> h[i];
  for (int i = 0; i < n; i++) {
		cin >> c[i];
		if (i) c[i] += c[i - 1];
	}
	LiChao hull(MAX_N);
	dp[0] = 0;
	hull.add({-2 * h[0], dp[0] - c[0] + h[0] * h[0]}, 0, MAX_N, 0);
  for (int i = 1; i < n; i++) dp[i] = 1e18;
  for (int i = 1; i < n; i++) {
		dp[i] = hull.get(0, MAX_N, 0, h[i]);
		dp[i] += h[i] * h[i] + (i - 1 >= 0 ? c[i - 1] : 0);
		hull.add({-2 * h[i], dp[i] - c[i] + h[i] * h[i]}, 0, MAX_N, 0);
	} 
  cout << dp[n - 1] << '\n';
  return 0;
}

• Subtask 1: 0 / 30
• Subtask 2: 0 / 30
• Subtask 3: 0 / 40