Submission #743148

#	Time	Username	Problem	Language	Result	Execution time	Memory
743148		vjudge1	Lightning Rod (NOI18_lightningrod)	C++17	40 / 100	2084 ms	262144 KiB

Main

#include <bits/stdc++.h>
using namespace std;
vector<pair<int, int>> v;

bool sorted(const pair<int, int> &a, const pair<int, int> &b)
{
    if (a.second == b.second)
        return a.first > b.first;
    return a.second > b.second;
}

bool check(int x1, int x2, int y1, int y2)
{
    return abs(x1 - x2) <= y1 - y2;
}

inline void read(int &x)
{
    x = 0;
    char ch = getchar_unlocked();
    while (ch & 16)
    {
        x = (x << 3) + (x << 1) + (ch & 15);
        ch = getchar_unlocked();
    }
}

int main()
{
    // bf
    map<int, int> ma;
    map<int, int> poled;
    int n, a, b;
    read(n);
    for (int i = 1; i <= n; ++i)
    {
        read(a);
        read(b);
        v.push_back({a, b});
        ma[i - 1] = -1;
        poled[i - 1] = 0;
    }
    sort(v.begin(), v.end(), sorted);
    for (int i = 0; i < v.size(); ++i)
    {
        for (int j = 0; j < v.size(); ++j)
        {
            if (i != j && check(v[i].first, v[j].first, v[i].second, v[j].second))
            {
                ma[j] = i;
            }
        }
    }
    long long sum = 0;
    for (auto it = ma.begin(); it != ma.end(); ++it)
    {
        if (it->second == -1)
        {
            sum++;
            poled[it->first] = 1;
        }
        else
        {
            poled[it->first] = 1;
        }
    }
    cout << sum;
}

Compilation message (stderr)

lightningrod.cpp: In function 'int main()':
lightningrod.cpp:44:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   44 |     for (int i = 0; i < v.size(); ++i)
      |                     ~~^~~~~~~~~~
lightningrod.cpp:46:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   46 |         for (int j = 0; j < v.size(); ++j)
      |                         ~~^~~~~~~~~~

• Subtask 1: 0 / 4
• Subtask 2: 7 / 7
• Subtask 3: 12 / 12
• Subtask 4: 21 / 21
• Subtask 5: 0 / 26
• Subtask 6: 0 / 10
• Subtask 7: 0 / 20