oj.uz

답안 #923796

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
923796 2024-02-07T19:10:39 Z Karoot Building Bridges (CEOI17_building) C++17
100 / 100
 38 ms 11792 KB 
#include <iostream>
#include <cmath>
#include <unordered_map>
#include <map>
#include <set>
#include <queue>
#include <vector>
#include <string>
#include <iomanip>
#include <algorithm>
#include <climits>

#define all(x)  (x).begin(), (x).end()
#define rall(x)  (x).rbegin(), (x).rend()

using namespace std;

typedef long long ll;

ll linf = 1e15+1;

inline void scoobydoobydoo(){
    ios::sync_with_stdio(false);
    ios_base::sync_with_stdio(false);
    cin.tie(NULL); cout.tie(NULL);
}

struct Line {
	mutable ll k, m, p;
	bool operator<(const Line& o) const { return k < o.k; }
	bool operator<(ll x) const { return p < x; }
};

struct LineContainer : multiset<Line, less<>> {
	// (for doubles, use inf = 1/.0, div(a,b) = a/b)
	static const ll inf = LLONG_MAX;
	ll div(ll a, ll b) { // floored division
		return a / b - ((a ^ b) < 0 && a % b); }
	bool isect(iterator x, iterator y) {
		if (y == end()) return x->p = inf, 0;
		if (x->k == y->k) x->p = x->m > y->m ? inf : -inf;
		else x->p = div(y->m - x->m, x->k - y->k);
		return x->p >= y->p;
	}
	void add(ll k, ll m) {
		auto z = insert({k, m, 0}), y = z++, x = y;
		while (isect(y, z)) z = erase(z);
		if (x != begin() && isect(--x, y)) isect(x, y = erase(y));
		while ((y = x) != begin() && (--x)->p >= y->p)
			isect(x, erase(y));
	}
	ll query(ll x) {
		if (empty())return -linf;
		auto l = *lower_bound(x);
		return l.k * x + l.m;
	}
};

LineContainer LC;

const int MAXN = 2e5+1;

ll mem[MAXN];
ll pref[MAXN];
ll heights[MAXN];
int n;

ll dp(){
    mem[0] = 0;
    LC.add(2*heights[0], -pow(heights[0],2)+pref[0]);
    //cout << mem[0] << " ";
    for (int i = 1; i < n; i++){
        mem[i] = pref[i-1]+pow(heights[i], 2)-LC.query(heights[i]);
        //cout << mem[i] << " ";
        LC.add(2*heights[i], -mem[i]-pow(heights[i], 2)+pref[i]);
    }
    //cout << endl;
    return mem[n-1];
}

int main(){
    scoobydoobydoo();
    cin >> n;
    for (int i = 0; i < n; i++) cin >> heights[i];
    for (int i = 0; i < n; i++){
        cin >> pref[i];
        pref[i] += (i == 0 ? 0 : pref[i-1]);
    }

    cout << dp() << endl;


    return 0;
}

Subtask #1
30.0 / 30.0

# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 4444 KB Output is correct
2 Correct 1 ms 4444 KB Output is correct
3 Correct 1 ms 4444 KB Output is correct
4 Correct 2 ms 4580 KB Output is correct
5 Correct 1 ms 4440 KB Output is correct

Subtask #2
30.0 / 30.0

# 결과 실행 시간 메모리 Grader output
1 Correct 30 ms 5728 KB Output is correct
2 Correct 30 ms 5720 KB Output is correct
3 Correct 30 ms 5720 KB Output is correct
4 Correct 29 ms 5464 KB Output is correct
5 Correct 26 ms 7000 KB Output is correct

Subtask #3
40.0 / 40.0

# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 4444 KB Output is correct
2 Correct 1 ms 4444 KB Output is correct
3 Correct 1 ms 4444 KB Output is correct
4 Correct 2 ms 4580 KB Output is correct
5 Correct 1 ms 4440 KB Output is correct
6 Correct 30 ms 5728 KB Output is correct
7 Correct 30 ms 5720 KB Output is correct
8 Correct 30 ms 5720 KB Output is correct
9 Correct 29 ms 5464 KB Output is correct
10 Correct 26 ms 7000 KB Output is correct
11 Correct 29 ms 5720 KB Output is correct
12 Correct 30 ms 5724 KB Output is correct
13 Correct 25 ms 5740 KB Output is correct
14 Correct 31 ms 5724 KB Output is correct
15 Correct 38 ms 11792 KB Output is correct
16 Correct 26 ms 6748 KB Output is correct
17 Correct 16 ms 5724 KB Output is correct
18 Correct 16 ms 5724 KB Output is correct