답안 #468840

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
468840 2021-08-29T19:49:31 Z mychecksedad Exam (eJOI20_exam) C++17
77 / 100
231 ms 98972 KB
#include <bits/stdc++.h>
using namespace std;
const int N = 1e5+10, K = 20;
#define pb push_back
#define all(v) v.begin(), v.end()
int n, a[N], b[N], rmq[N][K];
map<int, vector<int>> m;

int subtask2(){
	int ans = 0;
	vector<bool> is_taken(n + 5, 0);
	for(int i = 1; i <= n; i++){
		if(a[i] == b[1]){
			ans++;
			int l = i-1, r = i + 1;
			is_taken[i] = 1;
			for(; l >= 1 && !is_taken[l] && a[l] < b[1]; l--) ans++, is_taken[l] = 1;
			for(; r <= n && !is_taken[r] && a[r] < b[1]; r++) ans++, is_taken[r] = 1;
		}
	}
	return ans;
}
int Q(int l, int r){
	int k = __lg((r-l+1));
	return max(rmq[l][k], rmq[r - (1<<k) + 1][k]);
}
int subtask4(){
	map<int, int> m;
	for(int i = 1; i <= n; i++) m[a[i]] = i;
	vector<int> dp(n+2), v(1), lis(1);
	for(int i = 1; i <= n; i++){
		if(a[i] <= b[i]){
			int pos = m[b[i]];
			if(pos > 0 && Q(min(i, pos), max(i, pos)) <= b[i]){
				v.pb(pos);
			}
		}
	}	
	sort(all(v));
	int ans = 0;

	for(int i = 1; i < v.size(); i++){
		int l = lower_bound(all(lis), a[v[i]]) - lis.begin();
		if(l == lis.size()) lis.pb(l);
		else{
			lis[l] = a[v[i]];
		}
	}
	return int(lis.size())-1;
}
void precalc(){
	for(int i = 1; i <= n; i++) rmq[i][0] = a[i];
	for(int j = 1; j < K; j++){
		for(int i = 1; i + (1<<j) <= n + 1; i++){
			rmq[i][j] = max(rmq[i][j - 1], rmq[i + (1<<(j-1))][j - 1]);
		}
	}
}

int main(){
	cin.tie(0); ios::sync_with_stdio(0);
	cin >> n;
	for(int i = 1; i <= n; i++) cin >> a[i];
	for(int i = 1; i <= n; i++) cin >> b[i];
	precalc();
	bool is_b = 1;
	for(int i = 2; i <= n; i++) if(b[i] != b[i - 1]) is_b = 0;
	if(is_b){
		cout << subtask2();
		return 0;
	}
	if(n > 5000){
		cout << subtask4();
		return 0;
	}
	int ans = 0;
	vector<vector<int>> dp(n+2, vector<int>(n+2));
	for(int i = 1; i <= n; i++){
		int mx = 0;
		for(int j = 1; j <= n; j++){
			int x = Q(min(i, j), max(i, j));
			mx = max(mx, dp[i - 1][j]);
			if(x > b[i]){
				dp[i][j] = mx;
			}else{
				if(a[i] <= b[i] && a[j] == b[i]){
					dp[i][j] = mx + 1;
				}else dp[i][j] = mx;
			}
			if(i==n) ans=max(ans, dp[i][j]);
		}
	}


	cout << ans;


	return 0;
}

Compilation message

exam.cpp: In function 'int subtask4()':
exam.cpp:42:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   42 |  for(int i = 1; i < v.size(); i++){
      |                 ~~^~~~~~~~~~
exam.cpp:44:8: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   44 |   if(l == lis.size()) lis.pb(l);
      |      ~~^~~~~~~~~~~~~
exam.cpp:40:6: warning: unused variable 'ans' [-Wunused-variable]
   40 |  int ans = 0;
      |      ^~~
# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 332 KB Output is correct
2 Correct 0 ms 332 KB Output is correct
3 Correct 0 ms 332 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 1 ms 332 KB Output is correct
2 Correct 8 ms 1996 KB Output is correct
3 Correct 26 ms 8020 KB Output is correct
4 Correct 25 ms 8872 KB Output is correct
5 Correct 38 ms 8896 KB Output is correct
6 Correct 25 ms 8856 KB Output is correct
7 Correct 27 ms 9056 KB Output is correct
8 Correct 36 ms 8908 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 332 KB Output is correct
2 Correct 3 ms 1356 KB Output is correct
3 Correct 35 ms 16264 KB Output is correct
4 Correct 193 ms 91148 KB Output is correct
5 Correct 203 ms 98768 KB Output is correct
6 Correct 206 ms 98836 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Incorrect 3 ms 972 KB Output isn't correct
2 Halted 0 ms 0 KB -
# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 332 KB Output is correct
2 Correct 0 ms 332 KB Output is correct
3 Correct 0 ms 332 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 0 ms 332 KB Output is correct
9 Correct 1 ms 332 KB Output is correct
10 Correct 1 ms 460 KB Output is correct
11 Correct 1 ms 460 KB Output is correct
12 Correct 1 ms 460 KB Output is correct
13 Correct 1 ms 460 KB Output is correct
14 Correct 1 ms 460 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 332 KB Output is correct
2 Correct 0 ms 332 KB Output is correct
3 Correct 0 ms 332 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 332 KB Output is correct
8 Correct 3 ms 1356 KB Output is correct
9 Correct 35 ms 16264 KB Output is correct
10 Correct 193 ms 91148 KB Output is correct
11 Correct 203 ms 98768 KB Output is correct
12 Correct 206 ms 98836 KB Output is correct
13 Correct 0 ms 204 KB Output is correct
14 Correct 0 ms 332 KB Output is correct
15 Correct 1 ms 332 KB Output is correct
16 Correct 1 ms 460 KB Output is correct
17 Correct 1 ms 460 KB Output is correct
18 Correct 1 ms 460 KB Output is correct
19 Correct 1 ms 460 KB Output is correct
20 Correct 1 ms 460 KB Output is correct
21 Correct 1 ms 460 KB Output is correct
22 Correct 9 ms 4300 KB Output is correct
23 Correct 2 ms 716 KB Output is correct
24 Correct 231 ms 98968 KB Output is correct
25 Correct 203 ms 98852 KB Output is correct
26 Correct 208 ms 98884 KB Output is correct
27 Correct 203 ms 98852 KB Output is correct
28 Correct 200 ms 98816 KB Output is correct
29 Correct 208 ms 98972 KB Output is correct
30 Correct 211 ms 98736 KB Output is correct
31 Correct 212 ms 98756 KB Output is correct
32 Correct 203 ms 98756 KB Output is correct