Submission #974497

#	Time	Username	Problem	Language	Result	Execution time	Memory
974497		berr	Robot (JOI21_ho_t4)	C++17	34 / 100	3040 ms	49692 KiB

Main

#include <bits/stdc++.h>
using namespace std; 
#define int long long
const int N=5005, INF=1e18;

signed main(){
    ios_base::sync_with_stdio(false);
    cin.tie(0);
   
    int n, m; cin >> n >> m;

    vector<vector<array<int, 2>>> g(n);
    vector<int> c(m), p(m), id(m), u(m), v(m);
    vector<vector<int>> viss(n), diss(n);
    vector<int> pos_u(m), pos_v(m), dis(n, INF);

    for(int i=0; i<m; i++){
        cin >> u[i] >> v[i] >> c[i] >> p[i];
        u[i]--; v[i]--;

        if(u[i] > v[i]) swap(u[i], v[i]);
        g[u[i]].push_back({v[i], i});
        g[v[i]].push_back({u[i], i});

        viss[u[i]].push_back(0);
        viss[v[i]].push_back(0);
    }

    for(int i=0; i<n; i++){
        sort(g[i].begin(), g[i].end(), [&](auto x, auto y){
            return c[x[1]]<c[y[1]];
        });

        for(int l=0; l<g[i].size(); l++){
            auto [u, j]=g[i][l];
            if(i<u) pos_u[j] = l;
            else pos_v[j] = l;
        }
    }

    priority_queue<array<int, 3>> pq;
    pq.push({0, 0, -1});
    vector<int> vis(n);

    int ans = INF;

    while(pq.size()){
        auto [cost, ve, z] = pq.top();

        pq.pop(); 
        cost*=-1;
        if(z==-1 && dis[ve] < cost) continue;

        if(ve==n-1){ 
            ans=min(ans, cost);
            break;
        }
        int h=1;
        if(vis[ve]==0){
            vis[ve]++;
            h=0;

            int k=1;

            for(auto [i, j]: g[ve]){
                pq.push({-(cost+p[j]), i, j});
            }
            if(g[ve].size()){
            int tot=p[g[ve][0][1]];

            for(int l=1; l<g[ve].size(); l++){
                if(c[g[ve][l][1]]==c[g[ve][l-1][1]]){
                        k++;
                        tot+=p[g[ve][l][1]];
                    }
                    else{
                        for(int j=l-k; j<l; j++){
                             if(dis[g[ve][j][0]] > cost+tot-p[g[ve][j][1]]){
                                dis[g[ve][j][0]]=cost+tot-p[g[ve][j][1]];
                                pq.push({-(cost+tot-p[g[ve][j][1]]), g[ve][j][0], -1});
                            }                        
                        }
                        tot=p[g[ve][l][1]];
                        k=1;
                    }
                }

                for(int j=g[ve].size()-k; j<g[ve].size(); j++){
                    if(dis[g[ve][j][0]] > cost+tot-p[g[ve][j][1]]){
                        dis[g[ve][j][0]]=cost+tot-p[g[ve][j][1]];
                        pq.push({-(cost+tot-p[g[ve][j][1]]), g[ve][j][0], -1});
                    }
                }
            
            }

        }


        if(z==-1) continue;
    
        int pos=0;
        if(v[z]==ve) pos=pos_v[z];
        else pos = pos_u[z];
        

        if(viss[ve][pos]==1) continue;
        viss[ve][pos]=1;

        int count=0, id=-1;
        vector<int> aa;
        int tot=0;
        for(int i=pos-1; i>=0; i--){
            if(c[g[ve][i][1]]!=c[z]) break;
            tot+=p[g[ve][i][1]], aa.push_back(i);
        }
        for(int i=pos+1; i<g[ve].size(); i++){
            if(c[g[ve][i][1]]!=c[z]) break;
            tot+=p[g[ve][i][1]], aa.push_back(i);
        }

        if(aa.size()){
            for(auto l: aa){

                if(dis[g[ve][l][0]]>(cost+tot-p[g[ve][l][1]])){
                    dis[g[ve][l][0]] =(cost+tot-p[g[ve][l][1]]);
                    pq.push({-(cost+tot-p[g[ve][l][1]]), g[ve][l][0], -1});
                }
            }
        }


    
    };
    if(ans==INF) cout<<-1;
    else cout<<ans;

}

Compilation message (stderr)

Main.cpp: In function 'int main()':
Main.cpp:34:23: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::array<long long int, 2> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   34 |         for(int l=0; l<g[i].size(); l++){
      |                      ~^~~~~~~~~~~~
Main.cpp:71:27: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::array<long long int, 2> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   71 |             for(int l=1; l<g[ve].size(); l++){
      |                          ~^~~~~~~~~~~~~
Main.cpp:88:44: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::array<long long int, 2> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   88 |                 for(int j=g[ve].size()-k; j<g[ve].size(); j++){
      |                                           ~^~~~~~~~~~~~~
Main.cpp:117:27: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::array<long long int, 2> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  117 |         for(int i=pos+1; i<g[ve].size(); i++){
      |                          ~^~~~~~~~~~~~~
Main.cpp:58:13: warning: variable 'h' set but not used [-Wunused-but-set-variable]
   58 |         int h=1;
      |             ^
Main.cpp:110:13: warning: unused variable 'count' [-Wunused-variable]
  110 |         int count=0, id=-1;
      |             ^~~~~
Main.cpp:110:22: warning: unused variable 'id' [-Wunused-variable]
  110 |         int count=0, id=-1;
      |                      ^~

• Subtask 1: 34 / 34
• Subtask 2: 0 / 24
• Subtask 3: 0 / 42