Submission #1312513

#	Time	Username	Problem	Language	Result	Execution time	Memory
1312513		syanvu	Exam (eJOI20_exam)	C++20	12 / 100	34 ms	4484 KiB

exam

// #pragma optimize ("g",on)
// #pragma GCC optimize ("inline")
// #pragma GCC optimize ("Ofast")
// #pragma GCC optimize ("unroll-loops")
// #pragma GCC optimize ("03")
#include <bits/stdc++.h>

#define pb push_back
#define SS ios_base::sync_with_stdio(0);cin.tie(nullptr);cout.tie(nullptr);
#define int long long
#define all(v) v.begin(),v.end()
using namespace std;
mt19937 rnd(chrono::steady_clock::now().time_since_epoch().count());

const int N = 2e5 + 1, inf = 1e9, mod = 998244353;

int n;
int a[N], b[N];

void solve(){
    cin >> n;
    vector<int> v;
    for(int i = 1; i <= n; i++){
        cin >> a[i];
        v.push_back(a[i]);
    }
    for(int i = 1; i <= n; i++){
        cin >> b[i];
        v.push_back(b[i]);
    }
    sort(all(v));
    v.erase(unique(all(v)), v.end());
    for(int i = 1; i <= n; i++){ 
        a[i] = lower_bound(all(v), a[i]) - v.begin() + 1;
        b[i] = lower_bound(all(v), b[i]) - v.begin() + 1; 
    }
    int dp[n + 1] = {};
    int r = b[1];
    for(int i = 2; i <= n; i++){
        if(r != b[i]){
            r = -1;
            break;
        }
    }
    if(r > 0){
        int last = 0, ans = 0, ok = 0;
        for(int i = 1; i <= n; i++){
            if(r < a[i]){
                ok = 0;
                last = i;
            }
            else if(r == a[i] && !ok){
                ok = 1;
                ans += i - last;
            }
            else if(ok) ans++;
        }
        cout << ans;
        return;
    }
    int ans = 0;
    for(int i = 1; i <= n; i++){
        int cnt = 0;
        for(int j = i; j >= 1; j--){
            if(b[j] == a[i]) cnt++;
            dp[i] = max(dp[i], dp[j - 1] + cnt);
            ans = max(ans, dp[i]);
        }
    }
    cout << ans;
}

signed main(){
    SS
    // freopen("trains.in", "r", stdin);
    // freopen("trains.out", "w", stdout);

    int t = 1;
    // cin >> t;
    while(t--){
        solve();
    }
}

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