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Submission #463398

# Submission time Handle Problem Language Result Execution time Memory
463398 2021-08-11T05:43:23 Z amunduzbaev Exam (eJOI20_exam) C++14
55 / 100
 131 ms 1108 KB 
#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 <= 205){
		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));
				}
			}
		}

		for(int i=0;i<n;i++) res = max(res, dp[i]);
		cout<<res<<"\n";
	} else {
		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> cnt(n);
			for(int j=max(0, l-1);j<=r;j++){
				 if(b[j] == a[i]) cnt[j]++;
				 if(j + 1 < n) cnt[j+1] = cnt[j];
			}

			vector<int> pref(n);
			for(int i=max(0, l-1);i<=r;i++){
				pref[i] = max(pref[i], dp[i] - cnt[i]);
				if(i + 1 < n) pref[i+1] = pref[i];
			}

			for(int j=l;j<=r;j++){
				dp[j] = max(dp[j], cnt[j] + (j ? pref[j - 1] : 0));
			}
		}

		for(int i=0;i<n;i++) res = max(res, dp[i]);
		cout<<res<<"\n";
	}
}

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;
	
	int mx = 0, mn = 1e9;
	for(auto x : b) mx = max(mx, x), mn = min(mn, x);
	if(mx == mn){
		solve2(n, a, b);
		return;
	}
	
	if(n <= 5005){
		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
14.0 / 14.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 204 KB Output is correct
2 Correct 0 ms 204 KB Output is correct
3 Correct 0 ms 204 KB Output is correct
4 Correct 0 ms 204 KB Output is correct
5 Correct 0 ms 204 KB Output is correct
6 Correct 0 ms 204 KB Output is correct

Subtask #2
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 204 KB Output is correct
2 Correct 5 ms 460 KB Output is correct
3 Correct 18 ms 1028 KB Output is correct
4 Correct 15 ms 1104 KB Output is correct
5 Correct 46 ms 1108 KB Output is correct
6 Correct 16 ms 1108 KB Output is correct
7 Correct 17 ms 972 KB Output is correct
8 Correct 25 ms 1100 KB Output is correct

Subtask #3
13.0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 204 KB Output is correct
2 Correct 2 ms 204 KB Output is correct
3 Correct 23 ms 356 KB Output is correct
4 Correct 108 ms 332 KB Output is correct
5 Correct 131 ms 388 KB Output is correct
6 Correct 120 ms 388 KB Output is correct

Subtask #4
0 / 23.0

# Verdict Execution time Memory Grader output
1 Incorrect 11 ms 332 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #5
16.0 / 16.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 204 KB Output is correct
2 Correct 0 ms 204 KB Output is correct
3 Correct 0 ms 204 KB Output is correct
4 Correct 0 ms 204 KB Output is correct
5 Correct 0 ms 204 KB Output is correct
6 Correct 0 ms 204 KB Output is correct
7 Correct 1 ms 204 KB Output is correct
8 Correct 2 ms 332 KB Output is correct
9 Correct 1 ms 332 KB Output is correct
10 Correct 2 ms 588 KB Output is correct
11 Correct 1 ms 588 KB Output is correct
12 Correct 1 ms 588 KB Output is correct
13 Correct 1 ms 588 KB Output is correct
14 Correct 4 ms 588 KB Output is correct

Subtask #6
0 / 22.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 204 KB Output is correct
2 Correct 0 ms 204 KB Output is correct
3 Correct 0 ms 204 KB Output is correct
4 Correct 0 ms 204 KB Output is correct
5 Correct 0 ms 204 KB Output is correct
6 Correct 0 ms 204 KB Output is correct
7 Correct 0 ms 204 KB Output is correct
8 Correct 2 ms 204 KB Output is correct
9 Correct 23 ms 356 KB Output is correct
10 Correct 108 ms 332 KB Output is correct
11 Correct 131 ms 388 KB Output is correct
12 Correct 120 ms 388 KB Output is correct
13 Correct 1 ms 204 KB Output is correct
14 Correct 2 ms 332 KB Output is correct
15 Correct 1 ms 332 KB Output is correct
16 Correct 2 ms 588 KB Output is correct
17 Correct 1 ms 588 KB Output is correct
18 Correct 1 ms 588 KB Output is correct
19 Correct 1 ms 588 KB Output is correct
20 Correct 4 ms 588 KB Output is correct
21 Correct 1 ms 588 KB Output is correct
22 Incorrect 1 ms 204 KB Output isn't correct
23 Halted 0 ms 0 KB -