oj.uz

답안 #250714

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
250714 2020-07-18T20:45:54 Z Sorting Building Bridges (CEOI17_building) C++14
100 / 100
 102 ms 66552 KB 
#include <bits/stdc++.h>

using namespace std;

const int k_N = 1e5 + 3;
const int k_Max = 1e6 + 3;
const long long k_Inf = 1e18;

struct LiChaoTree{
    struct Line{
        
        long long a, b;
        Line(){}
        Line(long long a, long long b): a(a), b(b){}
        long long operator()(long long x){
            return a * x + b;
        }
    };

    Line lines[4 * k_Max];

    LiChaoTree(){
        for(int i = 0; i < 4 * k_Max; ++i)
            lines[i] = {0, k_Inf};
    }   

    //[l, r)
    void update(int idx, int l, int r, Line new_line){
        int mid = (l + r) >> 1;
        bool lb = new_line(l) < lines[idx](l);
        bool mb = new_line(mid) < lines[idx](mid);

        if(mb)
            swap(lines[idx], new_line);
        if(r - l == 1) return;
        if(lb != mb)
            update(2 * idx + 1, l, mid, new_line);
        else
            update(2 * idx + 2, mid, r, new_line);
    }

    long long get(int idx, int l, int r, int x){
        if(x < l || r < x) return k_Inf;
        if(r - l == 1) return lines[idx](x);

        int mid = (l + r) >> 1;
        return min(lines[idx](x), min(get(2 * idx + 1, l, mid, x), get(2 * idx + 2, mid, r, x)));
    }
};

int n;
long long h[k_N], w[k_N];

long long dp[k_N];
LiChaoTree li_chao;

int main(){
    ios::sync_with_stdio(false);
    cin.tie(NULL);

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

    dp[n - 1] = 0;
    li_chao.update(0, 0, k_Max, LiChaoTree::Line(-2 * h[n - 1], h[n - 1] * h[n - 1]));

    long long sum = 0;
    for(int i = n - 2; i >= 0; --i){
        dp[i] = li_chao.get(0, 0, k_Max, h[i]) + h[i] * h[i] + sum;
        sum += w[i];
        li_chao.update(0, 0, k_Max, LiChaoTree::Line(-2 * h[i], h[i] * h[i] + dp[i] - sum));
    }

    //dp[i] = min(sum + h[i] * h[i] - 2 * h[i] * h[j] + h[j] * h[j] + dp[j], dp[i]);

    cout << dp[0] << "\n";
}
/*
6
3 8 7 1 6 6
0 -1 9 1 2 0
*/

Subtask #1
30.0 / 30.0

# 결과 실행 시간 메모리 Grader output
1 Correct 30 ms 62976 KB Output is correct
2 Correct 35 ms 62976 KB Output is correct
3 Correct 31 ms 62916 KB Output is correct
4 Correct 31 ms 62968 KB Output is correct
5 Correct 31 ms 62968 KB Output is correct

Subtask #2
30.0 / 30.0

# 결과 실행 시간 메모리 Grader output
1 Correct 84 ms 65400 KB Output is correct
2 Correct 80 ms 66296 KB Output is correct
3 Correct 86 ms 66296 KB Output is correct
4 Correct 78 ms 66168 KB Output is correct
5 Correct 74 ms 66296 KB Output is correct

Subtask #3
40.0 / 40.0

# 결과 실행 시간 메모리 Grader output
1 Correct 30 ms 62976 KB Output is correct
2 Correct 35 ms 62976 KB Output is correct
3 Correct 31 ms 62916 KB Output is correct
4 Correct 31 ms 62968 KB Output is correct
5 Correct 31 ms 62968 KB Output is correct
6 Correct 84 ms 65400 KB Output is correct
7 Correct 80 ms 66296 KB Output is correct
8 Correct 86 ms 66296 KB Output is correct
9 Correct 78 ms 66168 KB Output is correct
10 Correct 74 ms 66296 KB Output is correct
11 Correct 94 ms 66552 KB Output is correct
12 Correct 89 ms 66424 KB Output is correct
13 Correct 84 ms 66424 KB Output is correct
14 Correct 94 ms 66424 KB Output is correct
15 Correct 74 ms 66168 KB Output is correct
16 Correct 102 ms 66168 KB Output is correct
17 Correct 72 ms 66424 KB Output is correct
18 Correct 68 ms 66424 KB Output is correct