oj.uz

Submission #1087855

# Submission time Handle Problem Language Result Execution time Memory
1087855 2024-09-13T10:19:53 Z mychecksedad Sprinklers (CEOI24_sprinklers) C++17
9 / 100
 484 ms 6572 KB 
#include<bits/stdc++.h>
using namespace std;
#define ll long long int
#define pb push_back
#define en cout << '\n'
#define vi vector<int>
#define pii pair<int, int>
#define ff first
#define ss second
#define all(x) x.begin(),x.end()
const int N = 1e5+100;


int n, m, a[N], b[N];
int dp[N][2], par[N][2];
int get(int l, int r){
	if(r < l) return 0;
	return upper_bound(b+1, b+1+m, r) - lower_bound(b+1, b+1+m, l);
}
int get_first(int l){
	int pos =	lower_bound(b+1, b+1+m, l) - b;
	if(pos == m+1) return 2e9;
	return b[pos]; 
}
void solve(){
	cin >> n >> m;
	vector<pii> v;
	for(int i = 1; i <= n; ++i){
		cin >> a[i];
		v.pb({a[i], 1});
	}
	for(int i = 1; i <= m; ++i){
		cin >> b[i];
		v.pb({b[i], 0});
	}
	sort(all(v));
	string soll;
	int l = 0, r = 1e9+2, ans = -1;
	while(l <= r){
		int k = l+r>>1;
		string sol = "";
		bool ok = 1;
		int last_covered = -2e9;
		dp[1][0] = get(-2e9, a[1] - k - 1) > 0 ? (int)(-2e9) : get_first(a[1] + 1);
		dp[1][1] = get(-2e9, a[1] - 1) > 0 ? (int)(-2e9) : get_first(a[1] + k + 1);
		for(int i = 2; i <= n ;++i){
			int L = a[i] - k, R = a[i];
			if(dp[i - 1][0] >= L){
				dp[i][0] = get_first(a[i] + 1);
				par[i][0] = 0;
			}else{
				dp[i][0] = -2e9;
			}

			if(dp[i - 1][0] >= a[i]){
				par[i][1] = 0;
				dp[i][1] = get_first(a[i] + k + 1);
			}else{
				dp[i][1] = dp[i - 1][0];
				par[i][1] = 0;
			}

			if(dp[i-1][1] >= L){
				if(dp[i][0] < get_first(a[i] + 1)){
					par[i][0] = 1;
				}
				dp[i][0] = max(dp[i][0], get_first(a[i] + 1));
			}else{
				dp[i][0] = max(dp[i][0], (int)(-2e9));
			}

			if(dp[i-1][1] >= a[i]){
				if(dp[i][1] < get_first(a[i] + k + 1)){
					par[i][1] = 1;
				}
				dp[i][1] = max(dp[i][1], get_first(a[i] + k + 1));
			}else{
				if(dp[i][1] < dp[i - 1][1]){
					dp[i][1] = dp[i - 1][1];
					par[i][1] = 1;
				}
			}
		}
		if(max(dp[n][0], dp[n][1]) == (int)2e9){
			ok = 1;
			int x = 0;
			if(dp[n][0] == 2e9) x = 0;
			else x = 1;
			sol += (x==0?'L':'R');
			for(int i = n - 1; i >= 1; --i){
				x = par[i + 1][x];
				sol += (x==0?'L':'R');
			}
			reverse(all(sol));	
		}
		else ok = 0;
		


		if(ok){
			ans = k;
			soll = sol;
			r = k - 1;
		}else{
			l = k + 1;
		}
	}

	cout << ans << '\n';
	if(ans != -1){
		cout << soll;
	}
}

int main(){
	cin.tie(0); ios::sync_with_stdio(0);
	solve();
	return 0;
}

Compilation message

Main.cpp: In function 'void solve()':
Main.cpp:40:12: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   40 |   int k = l+r>>1;
      |           ~^~
Main.cpp:47:22: warning: unused variable 'R' [-Wunused-variable]
   47 |    int L = a[i] - k, R = a[i];
      |                      ^
Main.cpp:43:7: warning: unused variable 'last_covered' [-Wunused-variable]
   43 |   int last_covered = -2e9;
      |       ^~~~~~~~~~~~

Subtask #0
0.0 / 0.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 344 KB Correct
2 Correct 0 ms 348 KB Correct

Subtask #1
3.0 / 3.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Correct
2 Correct 8 ms 2524 KB Correct
3 Correct 0 ms 348 KB Correct
4 Correct 9 ms 2780 KB Correct
5 Correct 9 ms 2780 KB Correct
6 Correct 0 ms 348 KB Correct
7 Correct 0 ms 348 KB Correct
8 Correct 3 ms 1112 KB Correct
9 Correct 0 ms 348 KB Correct

Subtask #2
6.0 / 6.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 344 KB Correct
2 Correct 20 ms 2652 KB Correct
3 Correct 35 ms 956 KB Correct
4 Correct 395 ms 6480 KB Correct
5 Correct 457 ms 6572 KB Correct
6 Correct 0 ms 344 KB Correct
7 Correct 0 ms 348 KB Correct
8 Correct 224 ms 6392 KB Correct
9 Correct 188 ms 6436 KB Correct
10 Correct 420 ms 6480 KB Correct
11 Correct 160 ms 4472 KB Correct
12 Correct 182 ms 3792 KB Correct
13 Correct 399 ms 5376 KB Correct
14 Correct 379 ms 5588 KB Correct
15 Correct 393 ms 5712 KB Correct
16 Correct 396 ms 5320 KB Correct

Subtask #3
0.0 / 17.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 344 KB Correct
2 Correct 0 ms 348 KB Correct
3 Correct 1 ms 344 KB Correct
4 Correct 1 ms 348 KB Correct
5 Incorrect 0 ms 348 KB User solution is worse than jury's solution
6 Halted 0 ms 0 KB -

Subtask #4
0.0 / 27.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 344 KB Correct
2 Correct 64 ms 2976 KB Correct
3 Incorrect 484 ms 6348 KB User solution is worse than jury's solution
4 Halted 0 ms 0 KB -

Subtask #5
0.0 / 47.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 344 KB Correct
2 Correct 0 ms 348 KB Correct
3 Correct 8 ms 2524 KB Correct
4 Correct 0 ms 348 KB Correct
5 Correct 9 ms 2780 KB Correct
6 Correct 9 ms 2780 KB Correct
7 Correct 0 ms 348 KB Correct
8 Correct 0 ms 348 KB Correct
9 Correct 3 ms 1112 KB Correct
10 Correct 0 ms 348 KB Correct
11 Correct 20 ms 2652 KB Correct
12 Correct 35 ms 956 KB Correct
13 Correct 395 ms 6480 KB Correct
14 Correct 457 ms 6572 KB Correct
15 Correct 0 ms 344 KB Correct
16 Correct 0 ms 348 KB Correct
17 Correct 224 ms 6392 KB Correct
18 Correct 188 ms 6436 KB Correct
19 Correct 420 ms 6480 KB Correct
20 Correct 160 ms 4472 KB Correct
21 Correct 182 ms 3792 KB Correct
22 Correct 399 ms 5376 KB Correct
23 Correct 379 ms 5588 KB Correct
24 Correct 393 ms 5712 KB Correct
25 Correct 396 ms 5320 KB Correct
26 Correct 1 ms 344 KB Correct
27 Correct 1 ms 348 KB Correct
28 Incorrect 0 ms 348 KB User solution is worse than jury's solution
29 Halted 0 ms 0 KB -