Submission #1080394

#	Time	Username	Problem	Language	Result	Execution time	Memory
1080394		raphaelp	Fire (BOI24_fire)	C++14	0 / 100	1 ms	600 KiB

Main

#include <bits/stdc++.h>
using namespace std;
int main()
{
    long long N, M;
    cin >> N >> M;
    vector<vector<long long>> Tab;
    vector<pair<long long, long long>> input;
    for (long long i = 0; i < N; i++)
    {
        long long l, r;
        cin >> l >> r;
        input.push_back({l, r});
        if (r >= l)
        {
            Tab.push_back({l, r, i});
            Tab.push_back({l + M, r + M, i});
        }
        else
        {
            Tab.push_back({l, r + M, i});
        }
    }
    sort(Tab.begin(), Tab.end());
    long long last = -1;
    vector<long long> removed(Tab.size());
    for (long long i = 0; i < Tab.size(); i++)
    {
        if (last != -1)
        {
            if (Tab[last][1] >= Tab[i][1])
                removed[i] = 1;
        }
        if (removed[i] == 0)
            last = i;
    }
    vector<vector<long long>> Tab2;
    for (long long i = 0; i < Tab.size(); i++)
        if (!removed[i])
            Tab2.push_back(Tab[i]);
    swap(Tab, Tab2);
    vector<vector<pair<long long, long long>>> next(log2(N) + 1, vector<pair<long long, long long>>(N));
    for (long long i = Tab.size() - 1; i >= 0; i--)
    {
        long long x = lower_bound(Tab.begin(), Tab.end(), vector<long long>{Tab[i][1] + 1}) - Tab.begin() - 1;
        if (x != i)
        {
            next[0][Tab[i][2]].first = Tab[x][2];
            next[0][Tab[i][2]].second = Tab[x][1] - Tab[i][1];
        }
    }
    for (long long i = 1; i <= log2(N); i++)
    {
        for (long long j = 0; j < N; j++)
        {
            next[i][j].first = next[i - 1][next[i - 1][j].first].first;
            next[i][j].second = next[i - 1][j].second + next[i - 1][next[i - 1][j].first].second;
        }
    }
    long long best = 1000000000;
    for (long long i = 0; i < N; i++)
    {
        long long x = i, compte = 0, dist = 0;
        for (long long j = log2(N); j >= 0; j--)
        {
            if (dist + next[j][x].second < M)
            {
                dist += next[j][x].second;
                x = next[j][x].first;
                compte += (1 << j);
            }
        }
        if (dist + next[0][x].second >= M)
            best = min(best, compte + 1);
    }
    cout << ((best == 1000000000) ? -1 : best);
}

Compilation message (stderr)

Main.cpp: In function 'int main()':
Main.cpp:27:29: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::vector<long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   27 |     for (long long i = 0; i < Tab.size(); i++)
      |                           ~~^~~~~~~~~~~~
Main.cpp:38:29: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::vector<long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   38 |     for (long long i = 0; i < Tab.size(); i++)
      |                           ~~^~~~~~~~~~~~

• Subtask 1: 0 / 14
• Subtask 2: 0 / 17
• Subtask 3: 0 / 9
• Subtask 4: 0 / 13
• Subtask 5: 0 / 21
• Subtask 6: 0 / 26