Submission #1087864

# Submission time Handle Problem Language Result Execution time Memory
1087864 2024-09-13T10:31:50 Z mychecksedad Sprinklers (CEOI24_sprinklers) C++17
100 / 100
558 ms 6780 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 ? b[1] : get_first(a[1] + 1);
		dp[1][1] = get(-2e9, a[1] - 1) > 0 ? b[1] : 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(max(a[i - 1] + k + 1, a[i] + 1))){
					par[i][0] = 1;
				}
				dp[i][0] = max(dp[i][0], get_first(max(a[i - 1] + k + 1, 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;
		
		// cout << k << '\n';
		// for(int i = 1; i <= n; ++i) cout << dp[i][0] << ' ' << dp[i][1] << '\n';

		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;
      |       ^~~~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 1 ms 348 KB Correct
2 Correct 0 ms 460 KB Correct
# Verdict Execution time Memory Grader output
1 Correct 0 ms 460 KB Correct
2 Correct 8 ms 2524 KB Correct
3 Correct 1 ms 348 KB Correct
4 Correct 9 ms 2780 KB Correct
5 Correct 12 ms 2776 KB Correct
6 Correct 0 ms 464 KB Correct
7 Correct 0 ms 348 KB Correct
8 Correct 2 ms 1116 KB Correct
9 Correct 0 ms 348 KB Correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 348 KB Correct
2 Correct 19 ms 2780 KB Correct
3 Correct 31 ms 856 KB Correct
4 Correct 370 ms 6596 KB Correct
5 Correct 421 ms 6596 KB Correct
6 Correct 0 ms 344 KB Correct
7 Correct 0 ms 344 KB Correct
8 Correct 210 ms 6636 KB Correct
9 Correct 204 ms 6596 KB Correct
10 Correct 358 ms 6596 KB Correct
11 Correct 171 ms 4500 KB Correct
12 Correct 173 ms 3936 KB Correct
13 Correct 363 ms 5376 KB Correct
14 Correct 353 ms 5576 KB Correct
15 Correct 370 ms 5832 KB Correct
16 Correct 357 ms 5320 KB Correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 348 KB Correct
2 Correct 0 ms 460 KB Correct
3 Correct 0 ms 600 KB Correct
4 Correct 1 ms 348 KB Correct
5 Correct 0 ms 348 KB Correct
6 Correct 0 ms 348 KB Correct
7 Correct 0 ms 348 KB Correct
8 Correct 0 ms 348 KB Correct
9 Correct 0 ms 348 KB Correct
10 Correct 0 ms 500 KB Correct
11 Correct 0 ms 348 KB Correct
12 Correct 0 ms 348 KB Correct
13 Correct 1 ms 348 KB Correct
14 Correct 1 ms 348 KB Correct
15 Correct 1 ms 344 KB Correct
16 Correct 0 ms 348 KB Correct
17 Correct 0 ms 348 KB Correct
18 Correct 1 ms 348 KB Correct
19 Correct 0 ms 348 KB Correct
20 Correct 0 ms 348 KB Correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 348 KB Correct
2 Correct 63 ms 3032 KB Correct
3 Correct 455 ms 6684 KB Correct
4 Correct 431 ms 6600 KB Correct
5 Correct 439 ms 6600 KB Correct
6 Correct 465 ms 6780 KB Correct
7 Correct 489 ms 6640 KB Correct
8 Correct 457 ms 6592 KB Correct
9 Correct 457 ms 6576 KB Correct
10 Correct 427 ms 6600 KB Correct
11 Correct 476 ms 6600 KB Correct
12 Correct 0 ms 344 KB Correct
13 Correct 0 ms 348 KB Correct
14 Correct 192 ms 4368 KB Correct
15 Correct 235 ms 4560 KB Correct
16 Correct 219 ms 4552 KB Correct
17 Correct 319 ms 5316 KB Correct
18 Correct 342 ms 5320 KB Correct
19 Correct 367 ms 5828 KB Correct
20 Correct 450 ms 6092 KB Correct
21 Correct 434 ms 6256 KB Correct
22 Correct 426 ms 6084 KB Correct
23 Correct 446 ms 6084 KB Correct
24 Correct 425 ms 6008 KB Correct
25 Correct 430 ms 5852 KB Correct
26 Correct 278 ms 3796 KB Correct
27 Correct 153 ms 2696 KB Correct
28 Correct 394 ms 5380 KB Correct
29 Correct 376 ms 5368 KB Correct
30 Correct 409 ms 5352 KB Correct
31 Correct 367 ms 5332 KB Correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 348 KB Correct
2 Correct 0 ms 460 KB Correct
3 Correct 8 ms 2524 KB Correct
4 Correct 1 ms 348 KB Correct
5 Correct 9 ms 2780 KB Correct
6 Correct 12 ms 2776 KB Correct
7 Correct 0 ms 464 KB Correct
8 Correct 0 ms 348 KB Correct
9 Correct 2 ms 1116 KB Correct
10 Correct 0 ms 348 KB Correct
11 Correct 19 ms 2780 KB Correct
12 Correct 31 ms 856 KB Correct
13 Correct 370 ms 6596 KB Correct
14 Correct 421 ms 6596 KB Correct
15 Correct 0 ms 344 KB Correct
16 Correct 0 ms 344 KB Correct
17 Correct 210 ms 6636 KB Correct
18 Correct 204 ms 6596 KB Correct
19 Correct 358 ms 6596 KB Correct
20 Correct 171 ms 4500 KB Correct
21 Correct 173 ms 3936 KB Correct
22 Correct 363 ms 5376 KB Correct
23 Correct 353 ms 5576 KB Correct
24 Correct 370 ms 5832 KB Correct
25 Correct 357 ms 5320 KB Correct
26 Correct 0 ms 600 KB Correct
27 Correct 1 ms 348 KB Correct
28 Correct 0 ms 348 KB Correct
29 Correct 0 ms 348 KB Correct
30 Correct 0 ms 348 KB Correct
31 Correct 0 ms 348 KB Correct
32 Correct 0 ms 348 KB Correct
33 Correct 0 ms 500 KB Correct
34 Correct 0 ms 348 KB Correct
35 Correct 0 ms 348 KB Correct
36 Correct 1 ms 348 KB Correct
37 Correct 1 ms 348 KB Correct
38 Correct 1 ms 344 KB Correct
39 Correct 0 ms 348 KB Correct
40 Correct 0 ms 348 KB Correct
41 Correct 1 ms 348 KB Correct
42 Correct 0 ms 348 KB Correct
43 Correct 0 ms 348 KB Correct
44 Correct 63 ms 3032 KB Correct
45 Correct 455 ms 6684 KB Correct
46 Correct 431 ms 6600 KB Correct
47 Correct 439 ms 6600 KB Correct
48 Correct 465 ms 6780 KB Correct
49 Correct 489 ms 6640 KB Correct
50 Correct 457 ms 6592 KB Correct
51 Correct 457 ms 6576 KB Correct
52 Correct 427 ms 6600 KB Correct
53 Correct 476 ms 6600 KB Correct
54 Correct 0 ms 344 KB Correct
55 Correct 0 ms 348 KB Correct
56 Correct 192 ms 4368 KB Correct
57 Correct 235 ms 4560 KB Correct
58 Correct 219 ms 4552 KB Correct
59 Correct 319 ms 5316 KB Correct
60 Correct 342 ms 5320 KB Correct
61 Correct 367 ms 5828 KB Correct
62 Correct 450 ms 6092 KB Correct
63 Correct 434 ms 6256 KB Correct
64 Correct 426 ms 6084 KB Correct
65 Correct 446 ms 6084 KB Correct
66 Correct 425 ms 6008 KB Correct
67 Correct 430 ms 5852 KB Correct
68 Correct 278 ms 3796 KB Correct
69 Correct 153 ms 2696 KB Correct
70 Correct 394 ms 5380 KB Correct
71 Correct 376 ms 5368 KB Correct
72 Correct 409 ms 5352 KB Correct
73 Correct 367 ms 5332 KB Correct
74 Correct 32 ms 2800 KB Correct
75 Correct 413 ms 6596 KB Correct
76 Correct 558 ms 6616 KB Correct
77 Correct 0 ms 348 KB Correct
78 Correct 144 ms 6548 KB Correct
79 Correct 369 ms 6728 KB Correct
80 Correct 175 ms 6684 KB Correct
81 Correct 218 ms 4520 KB Correct
82 Correct 254 ms 4552 KB Correct
83 Correct 232 ms 4592 KB Correct
84 Correct 42 ms 1760 KB Correct
85 Correct 378 ms 5588 KB Correct
86 Correct 441 ms 5712 KB Correct
87 Correct 361 ms 5312 KB Correct
88 Correct 12 ms 2780 KB Correct
89 Correct 11 ms 2780 KB Correct