Submission #556995

# Submission time Handle Problem Language Result Execution time Memory
556995 2022-05-04T14:14:59 Z timreizin Salesman (IOI09_salesman) C++17
100 / 100
1008 ms 59140 KB
#include <iostream>
#include <vector>
#include <algorithm>
#include <deque>
#include <set>
#include <string>
#include <numeric>
#include <cmath>
#include <cassert>
#include <array>
#include <numeric>

using namespace std;

using ll = long long;

class SegmentTree
{
private:
    
    int amount;
    vector<ll> tree;
    
    ll get(int a, int b, int l, int r, int v)
    {
        if (a > r || b < l) return -1e9;
        if (a == l && b == r) return tree[v];
        int m = (l + r) >> 1;
        return max(get(a, min(b, m), l, m, v << 1), get(max(a, m + 1), b, m + 1, r, (v << 1) + 1));
    }
    
    void build(int l, int r, int v)
    {
        if (l > r) return;
        if (l == r)
        {
            tree[v] = -1e9;
            return;
        }
        int m = (l + r) >> 1;
        build(l, m, v << 1);
        build(m + 1, r, (v << 1) + 1);
        tree[v] = max(tree[v << 1], tree[(v << 1) + 1]);
    }
    
    void update(int p, int l, int r, int v, ll value)
    {
        if (l > r) return;
        if (l == r)
        {
            tree[v] = value;
            return;
        }
        int m = (l + r) >> 1;
        if (p <= m) update(p, l, m, v << 1, value);
        else update(p, m + 1, r, (v << 1) + 1, value);
        tree[v] = max(tree[v << 1], tree[(v << 1) + 1]);
    }
    
public:
    
    SegmentTree(int n = 0) : amount(n)
    {
        tree.resize(4 * amount + 5);
        build(0, n - 1, 1);
    }
    
    ll get(int a, int b)
    {
        return get(a, b, 0, amount - 1, 1);
    }
    
    void update(int p, ll value)
    {
        update(p, 0, amount - 1, 1, value);
    }
};

int main()
{
    cin.tie(0)->sync_with_stdio(0);
    int n;
    ll d, u, s;
    cin >> n >> u >> d >> s;
    vector<tuple<int, ll, ll>> fairs(n);
    for (auto &[t, l, m] : fairs) cin >> t >> l >> m;
    sort(fairs.begin(), fairs.end());
    vector<vector<pair<ll, ll>>> times;
    int last = get<0>(fairs.front());
    times.push_back(vector<pair<ll, ll>>());
    for (auto [t, l, m] : fairs)
    {
        if (t != last) times.push_back(vector<pair<ll, ll>>());
        times.back().emplace_back(l, m);
        last = t;
    }
    vector<tuple<int, ll, ll>>().swap(fairs);
    ll res = 0;
    SegmentTree left(500002), right(500002);
    left.update(s, s * d);
    right.update(s, -s * u);
    for (auto &fairs : times)
    {
        vector<ll> dp(fairs.size(), -1e9);
        //in set - bestj + sum
        ll delta = 0, prev = fairs[0].first;
        set<ll> best;
        for (int i = 0; i < dp.size(); ++i)
        {
            delta -= d * (fairs[i].first - prev);
            best.insert(max(left.get(0, fairs[i].first) - d * fairs[i].first, right.get(fairs[i].first, 500001) + u * fairs[i].first) - delta);
            delta += fairs[i].second;
            prev = fairs[i].first;
            dp[i] = (*best.rbegin()) + delta;
            /*for (int j = i; j >= 0; --j)
            {
                sum += fairs[j].second;
                ll bestj = max(left.get(0, fairs[j].first) - d * fairs[j].first, right.get(fairs[j].first, 500001) + u * fairs[j].first);
                dp[i] = max(dp[i], bestj + sum - (fairs[i].first - fairs[j].first) * d);
            }*/
        }
        delta = 0;
        prev = fairs.back().first;
        best.clear();
        for (int i = (int)dp.size() - 1; i >= 0; --i)
        {
            delta -= u * (prev - fairs[i].first);
            best.insert(max(left.get(0, fairs[i].first) - d * fairs[i].first, right.get(fairs[i].first, 500001) + u * fairs[i].first) - delta);
            delta += fairs[i].second;
            prev = fairs[i].first;
            dp[i] = max(dp[i], (*best.rbegin()) + delta);
        }
        for (int i = 0; i < dp.size(); ++i)
        {
            ll move = (s < fairs[i].first ? u * (fairs[i].first - s) : d * (s - fairs[i].first));
            res = max(res, dp[i] - move);
            left.update(fairs[i].first, dp[i] + fairs[i].first * d);
            right.update(fairs[i].first, dp[i] - fairs[i].first * u);
        }
    }
    cout << res;
    return 0;
}
/*
4 5 3 100
2 80 100
20 125 130
10 75 150
5 120 110
*/
/*
4 5 3 100
1 80 100
1 125 130
1 75 150
1 120 110
*/
//125 + 90 -

Compilation message

salesman.cpp: In function 'int main()':
salesman.cpp:108:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  108 |         for (int i = 0; i < dp.size(); ++i)
      |                         ~~^~~~~~~~~~~
salesman.cpp:133:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  133 |         for (int i = 0; i < dp.size(); ++i)
      |                         ~~^~~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 18 ms 31644 KB Output is correct
2 Correct 20 ms 31560 KB Output is correct
3 Correct 22 ms 31604 KB Output is correct
4 Correct 21 ms 31700 KB Output is correct
5 Correct 25 ms 32032 KB Output is correct
6 Correct 55 ms 32640 KB Output is correct
7 Correct 135 ms 34368 KB Output is correct
8 Correct 202 ms 37076 KB Output is correct
9 Correct 313 ms 39856 KB Output is correct
10 Correct 520 ms 48084 KB Output is correct
11 Correct 678 ms 48068 KB Output is correct
12 Correct 806 ms 53612 KB Output is correct
13 Correct 739 ms 53556 KB Output is correct
14 Correct 976 ms 59056 KB Output is correct
15 Correct 822 ms 59140 KB Output is correct
16 Correct 1008 ms 59084 KB Output is correct
17 Correct 20 ms 31572 KB Output is correct
18 Correct 24 ms 31572 KB Output is correct
19 Correct 21 ms 31688 KB Output is correct
20 Correct 23 ms 31664 KB Output is correct
21 Correct 27 ms 31700 KB Output is correct
22 Correct 25 ms 31888 KB Output is correct
23 Correct 25 ms 31828 KB Output is correct
24 Correct 25 ms 31832 KB Output is correct
25 Correct 219 ms 33584 KB Output is correct
26 Correct 367 ms 37080 KB Output is correct
27 Correct 637 ms 41576 KB Output is correct
28 Correct 649 ms 41036 KB Output is correct
29 Correct 980 ms 40060 KB Output is correct
30 Correct 976 ms 45152 KB Output is correct