Submission #440446

#	Time	Username	Problem	Language	Result	Execution time	Memory
440446		prvocislo	Exam (eJOI20_exam)	C++17	100 / 100	214 ms	13880 KiB

exam

#include <bits/stdc++.h>
typedef long long ll;
using namespace std;
 
int main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);
    int n;
    cin >> n;
    vector<int> a(n), b(n);
    for (int i = 0; i < n; i++) cin >> a[i];
    for (int i = 0; i < n; i++) cin >> b[i];
    vector<vector<int> > v(n, vector<int>(2, -1));
    for (int it = 0; it < 2; it++) 
    {
        map<int, int> m;
        vector<pair<int, int>> stk; // {hodnota, index}
        for (int k = 0; k < n; k++)
        {
            int i = it ? n - k - 1 : k;
            while (!stk.empty() && a[i] > stk.back().first) 
                m[stk.back().first] = -1, stk.pop_back();
            stk.push_back({a[i], i}); m[a[i]] = i;
            if (m.count(b[i]) && m[b[i]] != -1)
                v[i][it] = m[b[i]];
        }
    }
    vector<int> u;
    for (int i = 0; i < n; i++)
    {
        if (v[i][1] != -1) u.push_back(v[i][1]);
        if (v[i][0] != -1 && v[i][0] != v[i][1]) u.push_back(v[i][0]);
    }
    vector<int> l;
    for (int i : u)
    {
        int id = upper_bound(l.begin(), l.end(), i) - l.begin();
        if (id == l.size()) l.push_back(i);
        else l[id] = i;
    }
    cout << l.size() << "\n";
    return 0;
}

Compilation message (stderr)

exam.cpp: In function 'int main()':
exam.cpp:39:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   39 |         if (id == l.size()) l.push_back(i);
      |             ~~~^~~~~~~~~~~

• Subtask 1: 14 / 14
• Subtask 2: 12 / 12
• Subtask 3: 13 / 13
• Subtask 4: 23 / 23
• Subtask 5: 16 / 16
• Subtask 6: 22 / 22