Submission #576674

#	Time	Username	Problem	Language	Result	Execution time	Memory
576674		vqpahmad	Exam (eJOI20_exam)	C++14	12 / 100	1108 ms	524288 KiB

exam

#include <bits/stdc++.h>
#define ll long long
#define endl '\n'
#define all(a) a.begin(),a.end()
#define mod (ll)(10000007)
using namespace std;
const int mx = 1e6 + 15;
vector<int> a;
vector<int> b;
int solve(int s, int e){
    if (e-s<=1) return 0;
    map<int,int> mp;
    int mid = (s+e)/2;
    int mx = -1;
    int cnt = 0;
    for (int i = mid-1;i>=s;i--){
        mp[b[i]]++;
        if (b[i]<=mx && binary_search(a.begin()+mid,a.begin()+e,b[i])){
            cnt+=mp[b[i]];
        }
        else if (mp[b[i]]>cnt&&binary_search(a.begin()+mid,a.begin()+e,b[i])){
            cnt = mp[b[i]];
            mx = b[i];
        }
    }
    int p = s;
    for (int i=mid;i<e;i++){
        if (a[i]==mx){
            p = i;
            break;
        }
    }
    return max(solve(s,mid)+solve(mid,e),cnt+solve(p,e));
}


int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    int n;
    cin >> n;
    vector<pair<int,int>> ab(n);
    a.resize(n);
    b.resize(n);
    bool flag = 1;
    bool ans = 0;
    for (int i=0;i<n;i++){
        cin >> ab[i].first;
        a[i] = ab[i].first;
    }
    for (int i=0;i<n;i++){
        cin >> ab[i].second;
        b[i] = ab[i].second;
        if (i){
            if (ab[i-1].second!=ab[i].second) flag = 0;
        }
    }
    for (int i=0;i<n;i++){
        if (ab[i].first==ab[i].second) ans = 1;
    }
    if (flag&&ans) {
        int cnt =0;
        for (int i=0;i<n;i++){
            if (ab[i].first==ab[i].second){
                int p = i;
                while (ab[p].first<=ab[i].second){
                    cnt++;
                    p--;
                    if (p==-1) break;
                }
                p = i+1;
                if (p!=n){
                    while (ab[p].first<=ab[i].second){
                        cnt++;
                        p++;
                        if (p==n) break;
                    }
                }
                i = p-1;
            }
        }
        cout << cnt ;
    }
    else {
        cout << solve(0,n);
    }

    
}

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