Submission #463525

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
463525	2021-08-11T09:42:51 Z	amunduzbaev	Exam (eJOI20_exam)	C++14	100 / 100	191 ms	8936 KB

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);
	int res = 0;
	for(int i=0;i<n;i++){
		int s = i, e = i;
		while(s + 1 < n && a[s + 1] <= a[i]) s++;
		while(e && a[e - 1] <= a[i]) e--;

		vector<int> cnt(n);
		for(int j=0;j<n;j++){
			if(j) cnt[j] = cnt[j-1];
			cnt[j] += (b[j] == a[i]);
		}

		vector<int> pref(n, -1e9);
		for(int j=e;j<n;j++){
			if(j) pref[j] = pref[j-1];
			pref[j] = max(pref[j], (j ? - cnt[j-1] + dp[j-1] : 0));
		}

		for(int r=s;r>=e;r--){
			dp[r] = max(dp[r], cnt[r] + pref[r]);
		}
	}
	
	for(int i=0;i<n;i++) res = max(res, dp[i]);
	cout<<res<<"\n";
}

struct ST{
	vector<int> tree;
	int n;
	ST(int n) :n(n) {
		tree.resize(4 * n);
	}
	
	void sett(int i, int v, int lx, int rx, int x){
		if(lx == rx){
			tree[x] = v;
			return;
		}
		
		int m = (lx + rx)>>1;
		if(i <= m) sett(i, v, lx, m, x<<1);
		else sett(i, v, m+1, rx, x<<1|1);
		
		tree[x] = max(tree[x<<1], tree[x<<1|1]);
	}
	
	void sett(int i, int v){
		sett(i, v, 0, n, 1);
	}
	
	int get(int l, int r, int lx, int rx, int x){
		if(lx > r || rx < l) return 0;
		if(lx >= l && rx <= r) return tree[x];
		int m = (lx + rx)>>1;
		return max(get(l, r, lx, m, x<<1), get(l, r, m+1, rx, x<<1|1));
	}
	
	int get(int l, int r){
		if(r < l) return 0;
		return get(l, r, 0, n, 1);
	}
}; 
 
void solve2(int n, vector<int>& a, vector<int>& b){
	int mn = 1e9, mx = 0;
	for(auto x : b) mn = min(mn, x), mx = max(mx, x);
	if(mx == mn){
		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";
		return;
	}
	
	//~ I DONT KNOW HOW TO SOLVE
	
	ST tree(n), lazy(n);
	
	map<int, int> pp;
	for(int i=0;i<n;i++) pp[a[i]] = i, lazy.sett(i, a[i]);
	
	for(int i=0;i<n;i++){
		if(pp.count(b[i])){
			int l = i, r = pp[b[i]];
			if(lazy.get(min(l, r), max(l, r)) > b[i]) continue;
			tree.sett(r, tree.get(0, r) + 1);
		} 
		
		//~ for(int i=0;i<n;i++) cout<<tree.get(i, i)<<" ";
		//~ cout<<"\n";
	}
	
	cout<<tree.get(0, n)<<"\n";
}

/*

3
2 1 0
2 2 1

*/
 
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 <= 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	Memory	Grader output
1	Correct	204 KB	Output is correct
2	Correct	204 KB	Output is correct
3	Correct	204 KB	Output is correct
4	Correct	204 KB	Output is correct
5	Correct	204 KB	Output is correct
6	Correct	204 KB	Output is correct

Subtask #2
12.0 / 12.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	4 ms	204 KB	Output is correct
2	Correct	5 ms	460 KB	Output is correct
3	Correct	18 ms	972 KB	Output is correct
4	Correct	14 ms	1116 KB	Output is correct
5	Correct	27 ms	1100 KB	Output is correct
6	Correct	16 ms	1112 KB	Output is correct
7	Correct	16 ms	1108 KB	Output is correct
8	Correct	26 ms	1108 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	27 ms	332 KB	Output is correct
4	Correct	171 ms	456 KB	Output is correct
5	Correct	166 ms	392 KB	Output is correct
6	Correct	184 ms	384 KB	Output is correct

Subtask #4
23.0 / 23.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	96 ms	332 KB	Output is correct
2	Correct	55 ms	3756 KB	Output is correct
3	Correct	148 ms	8936 KB	Output is correct
4	Correct	149 ms	8924 KB	Output is correct
5	Correct	151 ms	8904 KB	Output is correct
6	Correct	160 ms	8864 KB	Output is correct
7	Correct	139 ms	8908 KB	Output is correct
8	Correct	150 ms	8924 KB	Output is correct
9	Correct	136 ms	8920 KB	Output is correct
10	Correct	107 ms	8900 KB	Output is correct

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	0 ms	204 KB	Output is correct
9	Correct	1 ms	204 KB	Output is correct
10	Correct	1 ms	204 KB	Output is correct
11	Correct	1 ms	204 KB	Output is correct
12	Correct	1 ms	204 KB	Output is correct
13	Correct	1 ms	204 KB	Output is correct
14	Correct	1 ms	204 KB	Output is correct

Subtask #6
22.0 / 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	27 ms	332 KB	Output is correct
10	Correct	171 ms	456 KB	Output is correct
11	Correct	166 ms	392 KB	Output is correct
12	Correct	184 ms	384 KB	Output is correct
13	Correct	1 ms	204 KB	Output is correct
14	Correct	0 ms	204 KB	Output is correct
15	Correct	1 ms	204 KB	Output is correct
16	Correct	1 ms	204 KB	Output is correct
17	Correct	1 ms	204 KB	Output is correct
18	Correct	1 ms	204 KB	Output is correct
19	Correct	1 ms	204 KB	Output is correct
20	Correct	1 ms	204 KB	Output is correct
21	Correct	1 ms	204 KB	Output is correct
22	Correct	6 ms	204 KB	Output is correct
23	Correct	191 ms	384 KB	Output is correct
24	Correct	127 ms	332 KB	Output is correct
25	Correct	104 ms	384 KB	Output is correct
26	Correct	105 ms	332 KB	Output is correct
27	Correct	94 ms	384 KB	Output is correct
28	Correct	95 ms	452 KB	Output is correct
29	Correct	166 ms	388 KB	Output is correct
30	Correct	120 ms	392 KB	Output is correct
31	Correct	147 ms	388 KB	Output is correct
32	Correct	123 ms	388 KB	Output is correct

Submission #463525

Compilation message

Subtask #1 14.0 / 14.0

Subtask #2 12.0 / 12.0

Subtask #3 13.0 / 13.0

Subtask #4 23.0 / 23.0

Subtask #5 16.0 / 16.0

Subtask #6 22.0 / 22.0

Subtask #1
14.0 / 14.0

Subtask #2
12.0 / 12.0

Subtask #3
13.0 / 13.0

Subtask #4
23.0 / 23.0

Subtask #5
16.0 / 16.0

Subtask #6
22.0 / 22.0