Submission #791371

#	Time	Username	Problem	Language	Result	Execution time	Memory
791371		otarius	Exam (eJOI20_exam)	C++17	0 / 100	21 ms	39488 KiB

exam

#include <iostream>
#include <algorithm>
#include <vector>
#include <set>
#include <cstring>
#include <queue>
#include <map>
#include <cmath>
#include <iomanip>
using namespace std;

#define ff first
#define sc second
#define pb push_back
#define ll long long
#define pll pair<ll, ll>
#define pii pair <int, int>
#define ull unsigned long long

// #define int long long
// #define int unsigned long long

const ll inf = 1e9 + 7;
const ll weirdMod = 998244353;

map<int, int> mp; int rnk = 0;
int pref[5001][10000], dp[5001];
void solve() {
    int n;
    cin >> n;
    if (n > 5000) {
        int a[n + 1], b[n + 1];
        for (int i = 1; i <= n; i++)
            cin >> a[i];
        for (int i = 1; i <= n; i++)
            cin >> b[i];
        bool f = 0;
        for (int i = 1; i <= n; i++) {
            if (a[i] == b[i]) {
                f = 1; break;
            }
        } cout << (f ? n : 0);
        return;
    }
    set<int> st;
    int a[n + 1], b[n + 1];
    for (int i = 1; i <= n; i++) {
        cin >> a[i]; st.insert(a[i]);
    } for (int i = 1; i <= n; i++) {
        cin >> b[i]; st.insert(b[i]);
    } for (int v : st) mp[v] = rnk++;
    for (int i = 1; i <= n; i++) {
        a[i] = mp[a[i]]; b[i] = mp[b[i]];
        for (int j = 0; j < 10000; j++) {
            pref[i][j] = pref[i - 1][j];
        } pref[i][b[i]]++;
    } for (int j = 1; j <= n; j++) {
        int mx = 0;
        for (int i = j; i >= 1; i--) {
            mx = max(mx, a[i]);
            dp[j] = max(dp[j], dp[i - 1] + pref[j][mx] - pref[i - 1][mx]);
        }
    } int mx = 0;
    for (int i = 1; i <= n; i++)
        mx = max(mx, dp[i]);
    cout << mx;
}
int32_t main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr); cout.tie(nullptr);
    
    int t = 1;
    // cin >> t;
    while (t--) {
        solve();
        cout << '\n';
    }
    return 0;
}

• Subtask 1: 0 / 14
• Subtask 2: 0 / 12
• Subtask 3: 0 / 13
• Subtask 4: 0 / 23
• Subtask 5: 0 / 16
• Subtask 6: 0 / 22