oj.uz

Submission #944157

# Submission time Handle Problem Language Result Execution time Memory
944157 2024-03-12T09:13:29 Z tnknguyen_ Commuter Pass (JOI18_commuter_pass) C++14
40 / 100
 225 ms 26636 KB 
#include <bits/stdc++.h>
using namespace std;
#define endl '\n' 
#define pll pair<long long, long long>
 
const int sz = 1e5 + 5;
vector<pll> gr[sz];
long long n, m, S, T, U, V;
long long dp[5][sz];
long long d[5][sz];
 
//constants
long long INF;
long long ST;
 
 
// ------------- FUNCTIONS ------------- //
void Dijkstra(int s, int k){
    priority_queue<pll> q;
    d[k][s] = 0;
    q.push({0, s});
 
    while(q.size()){
        long long w, u;
        tie(w, u) = q.top();
        w = -w;
        q.pop();
 
        if(w > d[k][u]){
            continue;
        }
 
        for(pll p : gr[u]){
            long long v, c;
            tie(v, c) = p;
            if(w + c < d[k][v]){
                d[k][v] = w + c;
                q.push({-d[k][v], v});
            }
        }
    } 
}
 
vector<int> dag[sz];
int vi[sz];
void build_DAG(int v){
    vi[v] = 1;
    for(pll p : gr[v]){
        long long u, c;
        tie(u, c) = p;
        if(d[0][u] + c + d[1][v] == ST){
            dag[u].push_back(v);
            if(vi[u] == 0){
                build_DAG(u);
            }
        }
    }
}
 
void topo(int u){
    vi[u] = 2;
    for(int v : dag[u]){
        dp[1][u] = min(dp[1][u], dp[1][v]);
        dp[2][u] = min(dp[2][u], dp[2][v]);
 
        if(vi[v] != 2){
            topo(v);
        }
    }
}
 
// ------------- SUBTASK ------------- //
namespace SUB1{
    bool ok(){
        return (S == U);
    }
 
    void solve(){
        Dijkstra(V, 3);
 
        long long ans = 1e18;
        for(int i=1;i<=n;++i){
            if(d[0][i] + d[1][i] == d[0][T]){
                ans = min(ans, d[3][i]);
            }
        }
        cout<<ans;
        //--------------------
        exit(0);
    }
}
 
long long ds2[305][305]; 
namespace SUB2{ // n <= 300
    bool ok(){
        return (n <= 300);
    }
 
    void solve(){
 
        memset(ds2, 63, sizeof(ds2));
        for(int i=1;i<=n;++i){
            ds2[i][i] = 0;
            for(pll p : gr[i]){
                ds2[i][p.first] = p.second;
            }
        }
 
        // Floyd - Warshall
        for(int k=1;k<=n;++k){
            for(int i=1;i<=n;++i){
                for(int j=1;j<=n;++j){
                    ds2[i][j] = min(ds2[i][j], ds2[i][k] + ds2[k][j]);
                }
            }
        }
 
        long long ans = ds2[U][V];
        for(int i=1;i<=n;++i){
            for(int j=1;j<=n;++j){
                if(ds2[S][i] + ds2[i][j] + ds2[j][T] == ST){
                    ans = min(ans, ds2[U][i] + ds2[j][V]);
                    ans = min(ans, ds2[U][j] + ds2[i][V]);
                }
            }
        }
 
        cout<<ans;
        //----------------------
        exit(0);
    }
}
 
namespace SUB3{
    void solve(){
        build_DAG(T);
 
        Dijkstra(U, 3);
        Dijkstra(V, 4); 
        
        memset(dp, 63, sizeof(dp));
        // for(int i=1;i<=n;++i){
        //     dp[1][i] = d[3][i];
        //     dp[2][i] = d[4][i]; 
        // }
 
        topo(S);
        long long ans = d[3][V];
        for(int i=1;i<=n;++i){
            ans = min({ans, dp[1][i] + d[4][i], dp[2][i] + d[3][i]});
        }
        cout<<ans;
    }
}
 
int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
 
    //freopen("PATHLIB.inp","r",stdin);
    //freopen("PATHLIB.out","w",stdout);
 
    cin >> n >> m;
    cin >> S >> T;
    cin >> U >> V;
    for(int i=1;i<=m;++i){
        int u, v, c;
        cin>>u>>v>>c;
        gr[u].push_back({v, c});
        gr[v].push_back({u, c});
    }
 
    memset(d, 63, sizeof(d));
    INF = d[0][0];
 
    Dijkstra(S, 0);
    Dijkstra(T, 1);
    ST = d[0][T];
 
    if(SUB1::ok()){ //S == U
        SUB1::solve();
    }
    if(SUB2::ok()){ //n <= 300
        SUB2::solve();
    }
    SUB3::solve();
 
    return 0;
}

Subtask #1
16.0 / 16.0

# Verdict Execution time Memory Grader output
1 Correct 169 ms 25392 KB Output is correct
2 Correct 185 ms 24288 KB Output is correct
3 Correct 155 ms 25116 KB Output is correct
4 Correct 153 ms 25236 KB Output is correct
5 Correct 158 ms 23936 KB Output is correct
6 Correct 166 ms 25452 KB Output is correct
7 Correct 184 ms 24080 KB Output is correct
8 Correct 151 ms 23968 KB Output is correct
9 Correct 171 ms 24008 KB Output is correct
10 Correct 132 ms 23908 KB Output is correct
11 Correct 56 ms 16988 KB Output is correct
12 Correct 162 ms 24064 KB Output is correct

Subtask #2
0 / 15.0

# Verdict Execution time Memory Grader output
1 Incorrect 225 ms 26636 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #3
24.0 / 24.0

# Verdict Execution time Memory Grader output
1 Correct 34 ms 13440 KB Output is correct
2 Correct 32 ms 11868 KB Output is correct
3 Correct 28 ms 12068 KB Output is correct
4 Correct 39 ms 14684 KB Output is correct
5 Correct 34 ms 13400 KB Output is correct
6 Correct 29 ms 12124 KB Output is correct
7 Correct 29 ms 12192 KB Output is correct
8 Correct 29 ms 12124 KB Output is correct
9 Correct 29 ms 12120 KB Output is correct
10 Correct 33 ms 13404 KB Output is correct
11 Correct 36 ms 12060 KB Output is correct
12 Correct 28 ms 12120 KB Output is correct
13 Correct 28 ms 11868 KB Output is correct
14 Correct 29 ms 11868 KB Output is correct
15 Correct 29 ms 11868 KB Output is correct

Subtask #4
0 / 45.0

# Verdict Execution time Memory Grader output
1 Correct 169 ms 25392 KB Output is correct
2 Correct 185 ms 24288 KB Output is correct
3 Correct 155 ms 25116 KB Output is correct
4 Correct 153 ms 25236 KB Output is correct
5 Correct 158 ms 23936 KB Output is correct
6 Correct 166 ms 25452 KB Output is correct
7 Correct 184 ms 24080 KB Output is correct
8 Correct 151 ms 23968 KB Output is correct
9 Correct 171 ms 24008 KB Output is correct
10 Correct 132 ms 23908 KB Output is correct
11 Correct 56 ms 16988 KB Output is correct
12 Correct 162 ms 24064 KB Output is correct
13 Incorrect 225 ms 26636 KB Output isn't correct
14 Halted 0 ms 0 KB -