oj.uz

Submission #873894

# Submission time Handle Problem Language Result Execution time Memory
873894 2023-11-16T02:34:37 Z noiaint Building Bridges (CEOI17_building) C++17
100 / 100
 39 ms 15936 KB 
#include <bits/stdc++.h>
#define int long long

using namespace std;

#define file ""

#define mp make_pair
#define fi first
#define se second
#define all(x) x.begin(), x.end()

#define getbit(x, i) (((x) >> (i)) & 1)
#define bit(x) (1LL << (x))
#define popcount __builtin_popcountll

mt19937_64 rd(chrono::steady_clock::now().time_since_epoch().count());
int rand(int l, int r) {
	return l + rd() % (r - l + 1);
}

const int N = 1e6 + 5;
const int mod = (int)1e9 + 7; // 998244353;
const int lg = 25; // lg + 1
const int oo = 1e9;
const long long ooo = 1e18;

template<class X, class Y> bool mini(X &a, Y b) {
	return a > b ? (a = b, true) : false;
}
template<class X, class Y> bool maxi(X &a, Y b) {
	return a < b ? (a = b, true) : false;
}
void add(int &a, int b) {
	a += b;
	if (a >= mod) a -= mod;
	if (a < 0) a += mod;
}
 
struct line {
	mutable int a, b, p;
	bool operator < (const line &x) const {
		return a < x.a;
	}
	bool operator < (const int &x) const {
		return p < x;
	}
};
 
struct cht : multiset<line, less<>> {
	const int inf = LLONG_MAX;
	int div(int a, int b) {
		return a / b - ((a ^ b) < 0 && a % b);
	}
	bool intersect(iterator x, iterator y) {
		if (y == end()) {
			x->p = inf;
			return false;
		}
		if (x->a == y->a) {
			x->p = x->b > y->b ? inf : -inf;
		}
		else x->p = div(x->b - y->b, y->a - x->a);
		return x->p >= y->p;
	}
	void add(int a, int b) {
		a = -a;
		b = -b;
		auto z = insert({a, b, 0}), y = z++, x = y;
		while (intersect(y, z)) z = erase(z);
		if (x != begin() && intersect(--x, y)) intersect(x, y = erase(y));
		while ((y = x) != begin() && (--x)->p >= y->p) intersect(x, erase(y));
	}
	int get(int x) {
		auto l = *lower_bound(x);
		return -(l.a * x + l.b);
	}
} T;

int n;
int h[N], w[N];
int f[N];

signed main() {
	ios::sync_with_stdio(false);
	cin.tie(0);

	// freopen(file".inp", "r", stdin);
	// freopen(file".out", "w", stdout);

	cin >> n;
	int sum = 0;
	for (int i = 1; i <= n; ++i) cin >> h[i];
	for (int i = 1; i <= n; ++i) cin >> w[i], sum += w[i];

	f[1] = -w[1];
	T.add(-2 * h[1], h[1] * h[1] + f[1]);

	for (int i = 2; i <= n; ++i) {
		f[i] = T.get(h[i]) + h[i] * h[i] - w[i];
		T.add(-2 * h[i], h[i] * h[i] + f[i]);
	}

	cout << f[n] + sum;

	return 0;
}

/*
f[i] = ax + b + c
a : -2 * h[i]
b : h[i] * h[i] + f[i]
c : h[i] * h[i] - w[i]
*/

Subtask #1
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 4440 KB Output is correct
2 Correct 1 ms 4444 KB Output is correct
3 Correct 1 ms 4444 KB Output is correct
4 Correct 1 ms 4444 KB Output is correct
5 Correct 1 ms 4444 KB Output is correct

Subtask #2
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 31 ms 9816 KB Output is correct
2 Correct 31 ms 9904 KB Output is correct
3 Correct 31 ms 9816 KB Output is correct
4 Correct 28 ms 9564 KB Output is correct
5 Correct 26 ms 10844 KB Output is correct

Subtask #3
40.0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 4440 KB Output is correct
2 Correct 1 ms 4444 KB Output is correct
3 Correct 1 ms 4444 KB Output is correct
4 Correct 1 ms 4444 KB Output is correct
5 Correct 1 ms 4444 KB Output is correct
6 Correct 31 ms 9816 KB Output is correct
7 Correct 31 ms 9904 KB Output is correct
8 Correct 31 ms 9816 KB Output is correct
9 Correct 28 ms 9564 KB Output is correct
10 Correct 26 ms 10844 KB Output is correct
11 Correct 31 ms 9808 KB Output is correct
12 Correct 30 ms 9816 KB Output is correct
13 Correct 24 ms 9936 KB Output is correct
14 Correct 31 ms 10064 KB Output is correct
15 Correct 39 ms 15936 KB Output is correct
16 Correct 27 ms 10880 KB Output is correct
17 Correct 16 ms 9820 KB Output is correct
18 Correct 16 ms 9740 KB Output is correct