oj.uz

Submission #1024168

# Submission time Handle Problem Language Result Execution time Memory
1024168 2024-07-15T14:31:20 Z _callmelucian Building Bridges (CEOI17_building) C++14
100 / 100
 56 ms 19564 KB 
#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef long double ld;
typedef pair<ll,ll> pl;
typedef pair<int,int> pii;
typedef tuple<int,int,int> tt;

#define all(a) a.begin(), a.end()
#define filter(a) a.erase(unique(all(a)), a.end())

struct line {
    ll a, b;

    line() : a(0), b(0) {}
    line (ll a, ll b) : a(a), b(b) {}

    ll calc (ll x) { return a * x + b; }

    ll slope() { return a; }
};

struct liChao {
    vector<line> tr;

    liChao() {}
    liChao (int sz) : tr(sz + 1, line(0, LLONG_MAX)) {}

    void update (line f, int l, int r) {
        if (l > r) return;
        int mid = (l + r) >> 1;
        if (l == r) {
            tr[mid] = (f.calc(l) < tr[mid].calc(l) ? f : tr[mid]);
            return;
        }
        if (f.calc(mid) < tr[mid].calc(mid)) swap(tr[mid], f);
        if (f.slope() > tr[mid].slope())
            update(f, l, mid - 1); // case 1.1
        if (f.slope() < tr[mid].slope())
            update(f, mid + 1, r); // case 1.2
    }

    ll query (int p, int l, int r) {
        int mid = (l + r) >> 1;
        ll cur = tr[mid].calc(p);
        if (p == mid) return cur;
        if (p < mid) return min(query(p, l, mid - 1), cur);
        if (p > mid) return min(query(p, mid + 1, r), cur);
    }
};

const int M = 1e6 + 1;
ll dp[M], h[M], w[M];

ll f1 (int k) {
    return -2 * h[k];
}

ll f2 (int k) {
    return dp[k] + h[k] * h[k] - w[k];
}

ll f3 (int k) {
    return h[k] * h[k] + w[k - 1];
}

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

    int n; cin >> n;
    for (int i = 1; i <= n; i++) cin >> h[i];
    for (int i = 1; i <= n; i++) {
        cin >> w[i];
        w[i] += w[i - 1];
    }

    liChao tree(M);
    tree.update(line(f1(1), f2(1)), 0, M);

    for (int i = 2; i <= n; i++) {
        dp[i] = tree.query(h[i], 0, M) + f3(i);
        tree.update(line(f1(i), f2(i)), 0, M);
    }
    cout << dp[n];

    return 0;
}

Compilation message

building.cpp: In member function 'll liChao::query(int, int, int)':
building.cpp:50:5: warning: control reaches end of non-void function [-Wreturn-type]
   50 |     }
      |     ^

Subtask #1
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 7 ms 15960 KB Output is correct
2 Correct 7 ms 15964 KB Output is correct
3 Correct 7 ms 15964 KB Output is correct
4 Correct 7 ms 15964 KB Output is correct
5 Correct 7 ms 15964 KB Output is correct

Subtask #2
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 39 ms 19280 KB Output is correct
2 Correct 39 ms 19356 KB Output is correct
3 Correct 41 ms 19280 KB Output is correct
4 Correct 35 ms 19156 KB Output is correct
5 Correct 40 ms 19172 KB Output is correct

Subtask #3
40.0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 7 ms 15960 KB Output is correct
2 Correct 7 ms 15964 KB Output is correct
3 Correct 7 ms 15964 KB Output is correct
4 Correct 7 ms 15964 KB Output is correct
5 Correct 7 ms 15964 KB Output is correct
6 Correct 39 ms 19280 KB Output is correct
7 Correct 39 ms 19356 KB Output is correct
8 Correct 41 ms 19280 KB Output is correct
9 Correct 35 ms 19156 KB Output is correct
10 Correct 40 ms 19172 KB Output is correct
11 Correct 50 ms 19532 KB Output is correct
12 Correct 56 ms 19252 KB Output is correct
13 Correct 41 ms 19536 KB Output is correct
14 Correct 54 ms 19564 KB Output is correct
15 Correct 38 ms 19288 KB Output is correct
16 Correct 43 ms 19360 KB Output is correct
17 Correct 22 ms 19540 KB Output is correct
18 Correct 27 ms 19460 KB Output is correct