제출 #463387

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
463387		amunduzbaev	Exam (eJOI20_exam)	C++14	26 / 100	31 ms	1112 KiB

exam

#include "bits/stdc++.h"
using namespace std;

//~ #define int long long

void solve1(int n, vector<int>& a, vector<int>& b){
	vector<int> dp(n);
	if(n <= 5005){
		vector<array<int, 3>> tmp;
		for(int i=0;i<n;i++){
			tmp.push_back({a[i], 0, i});
			tmp.push_back({b[i], 1, i});
		}
		
		sort(tmp.begin(), tmp.end());
		for(int last=0, i=0;i<(int)tmp.size();){
			int j = i;
			while(j < (int)tmp.size() && tmp[j][0] == tmp[i][0]) j++;
			while(i < j){
				if(tmp[i][1]){
					b[tmp[i][2]] = last;
				} else {
					a[tmp[i][2]] = last;
				} i++; 
			} last++;
		}
		
		//~ for(int i=0;i<n;i++) cout<<a[i]<<" ";
		//~ cout<<endl;
		//~ for(int i=0;i<n;i++) cout<<b[i]<<" ";
		//~ cout<<endl;
		
		vector<vector<int>> cnt(2 * n, vector<int>(n));
		for(int i=0;i<n;i++){
			assert(b[i] < 2 * n);
			cnt[b[i]][i]++;
			if(i + 1 < n){
				for(int j=0;j<2*n;j++){
					cnt[j][i+1] = cnt[j][i];
				}
			}
		}

		//~ int res = 0;
		//~ for(int i=0;i<n;i++){
			//~ int s = i;
			//~ while(s + 1 < n && a[s + 1] <= a[i]) s++;
			//~ for(int r=s;r>=0;r--){
				//~ if(a[r] > a[i]) break;
				//~ for(int l=r;l>=0;l--){
					//~ if(a[l] > a[i]) break;
					//~ dp[r] = max(dp[r], cnt[a[i]][r] - (l ? cnt[a[i]][l-1] - dp[l-1] : 0));
					//~ res = max(res, dp[r]);
				//~ }
			//~ }
		//~ }
		
		int res = 0;
		for(int i=0;i<n;i++){
			int r = i, l = i;
			while(r + 1 < n && a[r + 1] <= a[i]) r++;
			while(l > 0 && a[l - 1] <= a[l]) l--;
			vector<int> tmp;
			for(int j=l;j<=r;j++) if(b[j] == a[i]) tmp.push_back(j);
			int mx = (l ? dp[l-1] : 0);
			for(int j=l;j<=r;j++){
				int in = upper_bound(tmp.begin(), tmp.end(), j) - tmp.begin();
				dp[j] = max(dp[j], in + mx);
				mx = max(mx, dp[j] - in);
			}
		}
		
		//~ for(int i=0;i<n;i++) cout<<dp[i]<<" ";
		//~ cout<<"\n";
		
		for(int i=0;i<n;i++) res = max(res, dp[i]);
		
		cout<<res<<"\n";
	} else {
		
	}
}

void solve2(int n, vector<int>& a, vector<int>& b){
	int last = 0, cnt = 0, res = 0;
	for(int i=0;i<n;i++){
		if(a[i] > b[0]){
			if(cnt){
				res += (i - last);
			}
			
			cnt = 0, last = i + 1;
		} else {
			cnt |= (a[i] == b[i]);
		}
	} if(cnt){
		res += (n - last);
	}
	
	cout<<res<<"\n";
}

void solve(){
	int n; cin>>n;
	vector<int> a(n), b(n);
	for(auto& x : a) cin>>x;
	for(auto& x : b) cin>>x;
	
	if(n <= 205){
		solve1(n, a, b);
	} else {
		solve2(n, a, b);
	}
}

/*

3
1 2 3
2 2 2

*/

signed main(){
	ios_base::sync_with_stdio(0); cin.tie(0);
	int t = 1;
	//~ cin>>t;
	while(t--) solve();
}

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