oj.uz

Submission #1077283

# Submission time Handle Problem Language Result Execution time Memory
1077283 2024-08-27T04:36:39 Z isaachew Railway Trip (JOI17_railway_trip) C++17
20 / 100
 2000 ms 17720 KB 
#include <bits/stdc++.h>
/*
 20p: just Dijkstra
 45p: keep left/right for each level (impossible to go past them)
 Cartesian tree-like
 
 Square root?
 
 
 */
int main(){
    std::ios::sync_with_stdio(0);
    std::cin.tie(0);
    std::vector<int> levels;
    int n,k,q;
    std::cin>>n>>k>>q;
    std::vector<std::vector<int>> edges(n);
    std::vector<std::vector<int>> bylevel(k);
    std::set<int> nums;
    for(int i=0;i<n;i++){
        int x;
        std::cin>>x;
        x--;
        levels.push_back(x);
        bylevel[x].push_back(i);
    }
    for(int i=k;i--;){
        for(int j=0;j<bylevel[i].size();j++){
            nums.insert(bylevel[i][j]);
        }
        for(int j=0;j<bylevel[i].size();j++){
            if(bylevel[i][j]!=0)edges[bylevel[i][j]].push_back(*--nums.lower_bound(bylevel[i][j]));
            if(bylevel[i][j]!=n-1)edges[bylevel[i][j]].push_back(*nums.upper_bound(bylevel[i][j]));
            //std::cout<<edges[bylevel[i][j]][0]<<'\n';
        }
    }
    for(int i=0;i<q;i++){
        int a,b;
        std::cin>>a>>b;
        a--,b--;
        
        std::vector<int> dists1(n,1e9),dists2(n,1e9);
        std::priority_queue<std::pair<int,int>> dijkstra;
        dijkstra.push({-0,a});
        while(!dijkstra.empty()){
            std::pair<int,int> cur=dijkstra.top();
            dijkstra.pop();
            if(dists1[cur.second]<=-cur.first)continue;
            dists1[cur.second]=-cur.first;
            for(int i:edges[cur.second]){
                dijkstra.push({cur.first-1,i});
            }
        }
        dijkstra.push({-0,b});
        while(!dijkstra.empty()){
            std::pair<int,int> cur=dijkstra.top();
            dijkstra.pop();
            if(dists2[cur.second]<=-cur.first)continue;
            dists2[cur.second]=-cur.first;
            for(int i:edges[cur.second]){
                dijkstra.push({cur.first-1,i});
            }
        }
        int mndst=1e9;
        for(int j=0;j<n;j++){
            //std::cout<<dists1[j]+dists2[j]<<'\n';
            mndst=std::min(mndst,dists1[j]+dists2[j]);
        }
        std::cout<<mndst-1<<'\n';
    }
}

Subtask #1
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 1 ms 344 KB Output is correct
4 Correct 1 ms 348 KB Output is correct
5 Correct 1 ms 348 KB Output is correct
6 Correct 1 ms 348 KB Output is correct
7 Correct 1 ms 348 KB Output is correct
8 Correct 1 ms 348 KB Output is correct
9 Correct 0 ms 348 KB Output is correct

Subtask #2
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 604 KB Output is correct
2 Correct 87 ms 12544 KB Output is correct
3 Correct 74 ms 12736 KB Output is correct
4 Correct 68 ms 12688 KB Output is correct
5 Correct 71 ms 12584 KB Output is correct
6 Correct 80 ms 12900 KB Output is correct
7 Correct 82 ms 16700 KB Output is correct
8 Correct 388 ms 14824 KB Output is correct
9 Correct 243 ms 15848 KB Output is correct
10 Correct 256 ms 13452 KB Output is correct
11 Correct 298 ms 15916 KB Output is correct
12 Correct 271 ms 14264 KB Output is correct
13 Correct 290 ms 13656 KB Output is correct
14 Correct 270 ms 15916 KB Output is correct
15 Correct 265 ms 14328 KB Output is correct
16 Correct 241 ms 13616 KB Output is correct
17 Correct 59 ms 15420 KB Output is correct
18 Correct 51 ms 15252 KB Output is correct
19 Correct 58 ms 17720 KB Output is correct

Subtask #3
0 / 25.0

# Verdict Execution time Memory Grader output
1 Execution timed out 2040 ms 12760 KB Time limit exceeded
2 Halted 0 ms 0 KB -

Subtask #4
0 / 55.0

# Verdict Execution time Memory Grader output
1 Execution timed out 2044 ms 17016 KB Time limit exceeded
2 Halted 0 ms 0 KB -