답안 #463525

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
463525 2021-08-11T09:42:51 Z amunduzbaev Exam (eJOI20_exam) C++14
100 / 100
191 ms 8936 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);
	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();
}
# 결과 실행 시간 메모리 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
# 결과 실행 시간 메모리 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
# 결과 실행 시간 메모리 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
# 결과 실행 시간 메모리 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
# 결과 실행 시간 메모리 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
# 결과 실행 시간 메모리 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