oj.uz

Submission #959841

# Submission time Handle Problem Language Result Execution time Memory
959841 2024-04-09T08:00:36 Z dosts Building Bridges (CEOI17_building) C++17
100 / 100
 37 ms 10588 KB 
//Dost SEFEROĞLU
#pragma GCC optimize("O3,unroll-loops,Ofast")
#include <bits/stdc++.h>
using namespace std;
#define int long long
#define pii pair<int,int>
#define ff first
#define ss second
#define sp << " " << 
#define vi vector<int>
const int N = 2e5+1,inf = 1e18;

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

struct CHT : multiset<Line, less<>> {
	int div(int a, int b) { // floored division
		return (a / b) - ((a ^ b) < 0 && a % b); 
    }
	bool intersect(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(int k, int m) {
		auto z = insert({k, m, 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 query(int x) {
		assert(!empty());
		auto l = *lower_bound(x);
		return l.k * x + l.m;
	}
};

void solve() {
    int n;
    cin >> n;
    vi h(n+1),w(n+1),W(n+1,0);
    for (int i=1;i<=n;i++) cin >> h[i];
    for (int i=1;i<=n;i++) cin >> w[i];
    for (int i=1;i<=n;i++) W[i] = W[i-1]+w[i];
    CHT cht;
    vi dp(n+1);
    cht.add(2*h[1],-h[1]*h[1]+W[1]);
    for (int i=2;i<=n;i++) {
        dp[i] = W[i-1]+h[i]*h[i]-cht.query(h[i]);
        cht.add(2*h[i],-h[i]*h[i]+W[i]-dp[i]);
    }
    cout << dp[n] << '\n';
}
                
                            
signed main() { 
    ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
    #ifdef Dodi
        freopen("in.txt","r",stdin);
        freopen("out.txt","w",stdout);
    #endif
    int t = 1;
    //cin >> t; 
    while (t --> 0) solve();
}

Subtask #1
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 344 KB Output is correct
2 Correct 1 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 1 ms 348 KB Output is correct
5 Correct 1 ms 348 KB Output is correct

Subtask #2
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 33 ms 4620 KB Output is correct
2 Correct 34 ms 4696 KB Output is correct
3 Correct 34 ms 4444 KB Output is correct
4 Correct 32 ms 4340 KB Output is correct
5 Correct 26 ms 5724 KB Output is correct

Subtask #3
40.0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 344 KB Output is correct
2 Correct 1 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 1 ms 348 KB Output is correct
5 Correct 1 ms 348 KB Output is correct
6 Correct 33 ms 4620 KB Output is correct
7 Correct 34 ms 4696 KB Output is correct
8 Correct 34 ms 4444 KB Output is correct
9 Correct 32 ms 4340 KB Output is correct
10 Correct 26 ms 5724 KB Output is correct
11 Correct 31 ms 4700 KB Output is correct
12 Correct 33 ms 4444 KB Output is correct
13 Correct 24 ms 4700 KB Output is correct
14 Correct 32 ms 4828 KB Output is correct
15 Correct 37 ms 10588 KB Output is correct
16 Correct 26 ms 5488 KB Output is correct
17 Correct 18 ms 4440 KB Output is correct
18 Correct 16 ms 4568 KB Output is correct