Submission #799682

#	Time	Username	Problem	Language	Result	Execution time	Memory
799682		n3rm1n	Exhibition (JOI19_ho_t2)	C++17	0 / 100	1 ms	212 KiB

joi2019_ho_t2

#include<bits/stdc++.h>
#define endl '\n'
using namespace std;
const int MAXN = 1e5 + 10;
void speed()
{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);
}
int n, m;
vector < pair < int , int > > g;
vector < int > frames;
void read()
{
    cin >> n >> m;
    int xx, yy;
    for (int i = 1; i <= n; ++ i)
    {
        cin >> xx >> yy;
        g.push_back(make_pair(yy, xx));
    }
    sort(g.begin(), g.end());
    for (int i = 1; i <= m; ++ i)
    {
        cin >> xx;
        frames.push_back(-xx);
    }
    sort(frames.begin(), frames.end());
}
vector < int > v;
bool check(int goal)
{
    v.clear();
    v.push_back(-1);
    int x;
    int sz = goal;
    for (int i = 0; i < g.size(); ++ i)
    {
        x = g[i].second;
        //cout << x << endl;
        //cout << (int)v.back() << endl;
        if(x >= (int)v.back() && x <= -frames[sz-1])
        {
            v.push_back(x);
            //cout << "in " << x << endl;
            sz --;
        }
        else
        {
            vector < int >::iterator it = upper_bound(v.begin(), v.end(), x);
            if(it == v.end())continue;
            int num = *it, index = it - v.begin();
            //cout << v[index] << " updated " << x << " on " << index << endl;

                v[index] = x;

        }
    }
   return (sz <= 0);
}
void bin_search()
{
    int l = 0, r = n, mid, ans = 0;
    while(l <= r)
    {
        mid = (l + r)/2;
        if(check(mid))
        {
            ans = mid;
            l = mid + 1;
        }
        else r = mid - 1;
    }
    cout << ans << endl;
}
int main()
{
    speed();

    read();
    bin_search();
    return 0;
}

Compilation message (stderr)

joi2019_ho_t2.cpp: In function 'bool check(int)':
joi2019_ho_t2.cpp:38:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   38 |     for (int i = 0; i < g.size(); ++ i)
      |                     ~~^~~~~~~~~~
joi2019_ho_t2.cpp:53:17: warning: unused variable 'num' [-Wunused-variable]
   53 |             int num = *it, index = it - v.begin();
      |                 ^~~

• Subtask 1: 0 / 10
• Subtask 2: 0 / 40
• Subtask 3: 0 / 50