Submission #1193996

#	Time	Username	Problem	Language	Result	Execution time	Memory
1193996		trvhung	Building Bridges (CEOI17_building)	C++20	100 / 100	52 ms	10928 KiB

building

#include <bits/stdc++.h>
// #include <ext/rope>
// #include <ext/pb_ds/assoc_container.hpp>

// using namespace __gnu_pbds;
// using namespace __gnu_cxx;
using namespace std;

// #define   ordered_set tree<int, null_type,less<int>, rb_tree_tag,tree_order_statistics_node_update>
#define            ll long long
#define           ull unsigned long long
#define            ld long double
#define            pb push_back
#define  bit(mask, i) ((mask >> i) & 1)
#define            el '\n'
#define             F first
#define             S second

template <class X, class Y> bool maximize(X &x, const Y &y) { return (x < y ? x = y, 1 : 0); }
template <class X, class Y> bool minimize(X &x, const Y &y) { return (x > y ? x = y, 1 : 0); }

const int INF = 1e9;
const ll LINF = 1e18;
const int MOD = 1e9 + 7;
const int MULTI = 0;
const ld eps = 1e-9;
const int dx[4] = {0, 1, 0, -1}, dy[4] = {1, 0, -1, 0}; // R D L U
const int ddx[4] = {-1, 1, 1, -1}, ddy[4] = {1, 1, -1, -1}; // UR DR DL UL
const char cx[4] = {'R', 'D', 'L', 'U'};
const ll base = 31;
const int nMOD = 2;
const ll mods[] = {(ll)1e9 + 10777, (ll)1e9 + 19777, (ll)1e9 + 3, (ll)1e9 + 3777};

const int N = 1e5 + 5;
const int M = 1e6;
int n, h[N], w[N];
ll p[N], dp[N];

struct line {
	ll a, b;
	line(ll a = 0, ll b = 0) : a(a), b(b) {}
	ll calc(ll x) {
		return a * x + b;
	}
};

struct LichaoTree {
	struct node {
		line tr;
		int lpt, rpt, l, r;
		node(int l = 0, int r = 0) : tr(0, LLONG_MIN), lpt(-1), rpt(-1), l(l), r(r) {}
	};

	vector<node> tree;
	int timer;

	LichaoTree(int l = 0, int r = 0) {
		timer = 0;
		tree.push_back(node(l, r));
	}

	void update(int id, line f) {
		if (tree[id].l == tree[id].r) {
			tree[id].tr = (f.calc(tree[id].l) > tree[id].tr.calc(tree[id].l) ? f : tree[id].tr);
			return;
		}

		int mid = (tree[id].l + tree[id].r) >> 1;

		if (f.calc(mid) > tree[id].tr.calc(mid)) swap(tree[id].tr, f);

		if (f.a < tree[id].tr.a) {
			if (tree[id].lpt == -1) tree[id].lpt = ++timer, tree.push_back(node(tree[id].l, mid));
			update(tree[id].lpt, f);
		}

		if (f.a > tree[id].tr.a) {
			if (tree[id].rpt == -1) tree[id].rpt = ++timer, tree.push_back(node(mid + 1, tree[id].r));
			update(tree[id].rpt, f);
		}
	}

	ll query(int id, int pos) {
		ll cur = tree[id].tr.calc(pos);
		int mid = (tree[id].l + tree[id].r) >> 1;
		if (tree[id].l == tree[id].r) return cur;

		if (pos <= mid)
			return max(cur, tree[id].lpt == -1 ? LLONG_MIN : query(tree[id].lpt, pos));
		else
			return max(cur, tree[id].rpt == -1 ? LLONG_MIN : query(tree[id].rpt, pos));
	}
};

void solve() {
	cin >> n;
	for (int i = 1; i <= n; ++i)
		cin >> h[i];
	for (int i = 1; i <= n; ++i)
		cin >> w[i], p[i] = p[i - 1] + w[i];

	LichaoTree LCT(0, M);
	LCT.update(0, line(2 * h[1], p[1] - 1LL * h[1] * h[1]));
	for (int i = 2; i <= n; ++i) {
		dp[i] = 1LL * h[i] * h[i] + p[i - 1] - LCT.query(0, h[i]);
		LCT.update(0, line(2 * h[i], p[i] - dp[i] - 1LL * h[i] * h[i]));
	}

	cout << dp[n];
}

signed main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);

    if (!MULTI) solve();
    else {
        int test; cin >> test;
        while (test--) solve();
    }
    
    return 0;
}

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