oj.uz

Submission #1074904

# Submission time Handle Problem Language Result Execution time Memory
1074904 2024-08-25T16:19:42 Z anton Sprinklers (CEOI24_sprinklers) C++17
100 / 100
 596 ms 8896 KB 
#include<bits/stdc++.h>

using namespace std;

#define int long long
#define pii pair<int, int>

vector<int> flowers;
vector<int> sprinklers;


int under(vector<int>& v, int x){
    int res =0;
    for(int step= (1<<20); step>=1; step/=2){
        if(res + step < v.size() && v[res+step]<=x){
            res+= step;
        }
    }

    return res;
}

int above(vector<int>& v, int x){
    int res =v.size()-1;
    for(int step= (1<<20); step>=1; step/=2){
        if(res - step >=0 && v[res-step]>=x){
            res-= step;
        }
    }
    return res;
}


pii get_coverage(pii interval){
    return {above(flowers, interval.first), under(flowers, interval.second)};
}

bool is_in(pii inter, int pos){
    return (pos>=inter.first && pos<=inter.second);
}

int N, M;

struct DP{
    int val= 0;
    int anc =0;
    string p;
    DP(){};
    DP(int _val, int _anc, string s){
        p = s;
        val = _val;
        anc= _anc;
    }
};

void chmax(DP& a, DP b){
    if(b.val>a.val){
        a= b;
    }
}

vector<DP> solve(int k){
    vector<DP> dp(N+1);

    for(int cur_sprinkler = 0; cur_sprinkler<N; cur_sprinkler++){
        int uncovered_flower = dp[cur_sprinkler].val;
        pii before_inter = get_coverage({sprinklers[cur_sprinkler]-k, sprinklers[cur_sprinkler]});
        if(is_in(before_inter, uncovered_flower)){
            chmax(dp[cur_sprinkler+1], DP(before_inter.second+1, cur_sprinkler, string("L")));
        }
        before_inter = get_coverage({sprinklers[cur_sprinkler], sprinklers[cur_sprinkler]+k});
        if(is_in(before_inter, uncovered_flower)){
            chmax(dp[cur_sprinkler+1], DP(before_inter.second+1, cur_sprinkler, string("R")));
        }

        if(cur_sprinkler<N-1){
            if(sprinklers[cur_sprinkler+1]-sprinklers[cur_sprinkler]<k){
                pii interval = {sprinklers[cur_sprinkler+1]-k, sprinklers[cur_sprinkler]+k};
                if(is_in(get_coverage(interval), uncovered_flower)){
                    chmax(dp[cur_sprinkler+2], DP(before_inter.second+1, cur_sprinkler, string("LR")));

                }
            }
        }

        chmax(dp[cur_sprinkler+1], DP(uncovered_flower, cur_sprinkler, string("R")));

    }

    return dp;
}

string res;
void backtrack(vector<DP>& dp, int pos){
    bool ok = true;
    while(ok){
        res.append(dp[pos].p.begin(), dp[pos].p.end());
        pos= dp[pos].anc;
        ok = pos>0;
    }
}
signed main(){
    cin>>N>>M;
    sprinklers.resize(N);

    for(int i = 0; i<N; i++){
        cin>>sprinklers[i];
    }

    int k;
    flowers.push_back(sprinklers[0]);
    for(int i = 0; i<M; i++){
        cin>>k;
        flowers.push_back(k);
    }

    flowers.push_back(sprinklers.back());

    sort(flowers.begin(), flowers.end());
    int K=1e9;

    if(solve(K).back().val != M+2){
        cout<<-1<<endl;
        return 0;
    }

    for(int step = (1<<30); step>=1; step/=2){
        if(K-step>=0 && solve(K-step).back().val == M+2){
            K-=step;
        }
    }

    cout<<K<<endl;
    auto res_dp = solve(K);
    backtrack(res_dp, N);

    reverse(res.begin(), res.end());

    cout<<res<<endl;
}

Compilation message

Main.cpp: In function 'long long int under(std::vector<long long int>&, long long int)':
Main.cpp:15:23: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   15 |         if(res + step < v.size() && v[res+step]<=x){
      |            ~~~~~~~~~~~^~~~~~~~~~

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 22 ms 2256 KB Correct
3 Correct 0 ms 348 KB Correct
4 Correct 28 ms 2268 KB Correct
5 Correct 29 ms 2256 KB Correct
6 Correct 0 ms 348 KB Correct
7 Correct 0 ms 348 KB Correct
8 Correct 5 ms 860 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 32 ms 1488 KB Correct
3 Correct 54 ms 900 KB Correct
4 Correct 543 ms 7024 KB Correct
5 Correct 494 ms 6768 KB Correct
6 Correct 0 ms 348 KB Correct
7 Correct 0 ms 348 KB Correct
8 Correct 533 ms 6892 KB Correct
9 Correct 567 ms 6868 KB Correct
10 Correct 564 ms 7024 KB Correct
11 Correct 312 ms 6096 KB Correct
12 Correct 260 ms 3276 KB Correct
13 Correct 389 ms 6516 KB Correct
14 Correct 396 ms 6764 KB Correct
15 Correct 417 ms 6696 KB Correct
16 Correct 421 ms 6684 KB Correct

Subtask #3
17.0 / 17.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 344 KB Correct
2 Correct 0 ms 348 KB Correct
3 Correct 0 ms 348 KB Correct
4 Correct 0 ms 432 KB Correct
5 Correct 1 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 1 ms 344 KB Correct
10 Correct 1 ms 348 KB Correct
11 Correct 0 ms 348 KB Correct
12 Correct 1 ms 344 KB Correct
13 Correct 1 ms 348 KB Correct
14 Correct 0 ms 348 KB Correct
15 Correct 0 ms 348 KB Correct
16 Correct 0 ms 348 KB Correct
17 Correct 1 ms 348 KB Correct
18 Correct 0 ms 348 KB Correct
19 Correct 0 ms 348 KB Correct
20 Correct 1 ms 348 KB Correct

Subtask #4
27.0 / 27.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 344 KB Correct
2 Correct 82 ms 1760 KB Correct
3 Correct 404 ms 6768 KB Correct
4 Correct 470 ms 6948 KB Correct
5 Correct 449 ms 6948 KB Correct
6 Correct 407 ms 6772 KB Correct
7 Correct 411 ms 6776 KB Correct
8 Correct 454 ms 6880 KB Correct
9 Correct 413 ms 6940 KB Correct
10 Correct 408 ms 6772 KB Correct
11 Correct 404 ms 6772 KB Correct
12 Correct 0 ms 348 KB Correct
13 Correct 0 ms 348 KB Correct
14 Correct 165 ms 6160 KB Correct
15 Correct 267 ms 6144 KB Correct
16 Correct 260 ms 6180 KB Correct
17 Correct 416 ms 6948 KB Correct
18 Correct 400 ms 6772 KB Correct
19 Correct 394 ms 6768 KB Correct
20 Correct 400 ms 6776 KB Correct
21 Correct 431 ms 6940 KB Correct
22 Correct 431 ms 6948 KB Correct
23 Correct 417 ms 6772 KB Correct
24 Correct 434 ms 6948 KB Correct
25 Correct 428 ms 6772 KB Correct
26 Correct 264 ms 5024 KB Correct
27 Correct 139 ms 2788 KB Correct
28 Correct 404 ms 6512 KB Correct
29 Correct 414 ms 6516 KB Correct
30 Correct 407 ms 6696 KB Correct
31 Correct 348 ms 5656 KB Correct

Subtask #5
47.0 / 47.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 344 KB Correct
2 Correct 0 ms 348 KB Correct
3 Correct 22 ms 2256 KB Correct
4 Correct 0 ms 348 KB Correct
5 Correct 28 ms 2268 KB Correct
6 Correct 29 ms 2256 KB Correct
7 Correct 0 ms 348 KB Correct
8 Correct 0 ms 348 KB Correct
9 Correct 5 ms 860 KB Correct
10 Correct 0 ms 348 KB Correct
11 Correct 32 ms 1488 KB Correct
12 Correct 54 ms 900 KB Correct
13 Correct 543 ms 7024 KB Correct
14 Correct 494 ms 6768 KB Correct
15 Correct 0 ms 348 KB Correct
16 Correct 0 ms 348 KB Correct
17 Correct 533 ms 6892 KB Correct
18 Correct 567 ms 6868 KB Correct
19 Correct 564 ms 7024 KB Correct
20 Correct 312 ms 6096 KB Correct
21 Correct 260 ms 3276 KB Correct
22 Correct 389 ms 6516 KB Correct
23 Correct 396 ms 6764 KB Correct
24 Correct 417 ms 6696 KB Correct
25 Correct 421 ms 6684 KB Correct
26 Correct 0 ms 348 KB Correct
27 Correct 0 ms 432 KB Correct
28 Correct 1 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 1 ms 344 KB Correct
33 Correct 1 ms 348 KB Correct
34 Correct 0 ms 348 KB Correct
35 Correct 1 ms 344 KB Correct
36 Correct 1 ms 348 KB Correct
37 Correct 0 ms 348 KB Correct
38 Correct 0 ms 348 KB Correct
39 Correct 0 ms 348 KB Correct
40 Correct 1 ms 348 KB Correct
41 Correct 0 ms 348 KB Correct
42 Correct 0 ms 348 KB Correct
43 Correct 1 ms 348 KB Correct
44 Correct 82 ms 1760 KB Correct
45 Correct 404 ms 6768 KB Correct
46 Correct 470 ms 6948 KB Correct
47 Correct 449 ms 6948 KB Correct
48 Correct 407 ms 6772 KB Correct
49 Correct 411 ms 6776 KB Correct
50 Correct 454 ms 6880 KB Correct
51 Correct 413 ms 6940 KB Correct
52 Correct 408 ms 6772 KB Correct
53 Correct 404 ms 6772 KB Correct
54 Correct 0 ms 348 KB Correct
55 Correct 0 ms 348 KB Correct
56 Correct 165 ms 6160 KB Correct
57 Correct 267 ms 6144 KB Correct
58 Correct 260 ms 6180 KB Correct
59 Correct 416 ms 6948 KB Correct
60 Correct 400 ms 6772 KB Correct
61 Correct 394 ms 6768 KB Correct
62 Correct 400 ms 6776 KB Correct
63 Correct 431 ms 6940 KB Correct
64 Correct 431 ms 6948 KB Correct
65 Correct 417 ms 6772 KB Correct
66 Correct 434 ms 6948 KB Correct
67 Correct 428 ms 6772 KB Correct
68 Correct 264 ms 5024 KB Correct
69 Correct 139 ms 2788 KB Correct
70 Correct 404 ms 6512 KB Correct
71 Correct 414 ms 6516 KB Correct
72 Correct 407 ms 6696 KB Correct
73 Correct 348 ms 5656 KB Correct
74 Correct 34 ms 2260 KB Correct
75 Correct 563 ms 8896 KB Correct
76 Correct 596 ms 8820 KB Correct
77 Correct 0 ms 604 KB Correct
78 Correct 539 ms 8788 KB Correct
79 Correct 545 ms 8820 KB Correct
80 Correct 564 ms 8816 KB Correct
81 Correct 298 ms 7132 KB Correct
82 Correct 339 ms 7160 KB Correct
83 Correct 331 ms 7132 KB Correct
84 Correct 40 ms 1492 KB Correct
85 Correct 445 ms 7932 KB Correct
86 Correct 428 ms 8048 KB Correct
87 Correct 373 ms 7064 KB Correct
88 Correct 27 ms 2260 KB Correct
89 Correct 29 ms 2256 KB Correct