Submission #587002

#	Time	Username	Problem	Language	Result	Execution time	Memory
587002		keertan	Robot (JOI21_ho_t4)	C++17	100 / 100	785 ms	82020 KiB

Main

// GH SAI KEERTAN
#include <bits/stdc++.h>

using namespace std;
#define int  int64_t
#define rep(Begin,End) for (Begin=0;Begin<(End);Begin++)
#define all(x) x.begin(), x.end()
#define all1(x) x.rbegin(), x.rend()
#define sz(x) (int32_t)(x.size())
const int32_t N = 1e5+4, mod =1e9+7;
const int64_t N1=1e18;
const double eps=1e-6,cmp=1e-3;

void solve(){
    int n,m;
    cin>>n>>m;
    int gh=n;
    vector<vector<pair<int,int>>> adj(n+2*m);
    map<pair<int,int>,int> mid;
    vector<int> sum(n+2*m);
    int cur=n;
    auto id=[&](int v,int c)->int{
        auto it=mid.insert({{v,c},n});
        n+=it.second;
        return it.first->second;
    };

    for (int i=1,u,v,c,p;i<=m;i++){
        cin>>u>>v>>c>>p;
        u--,v--;
        adj[u].emplace_back(v,p);
        adj[v].emplace_back(u,p);
        int uid=id(u,c),vid=id(v,c);

        sum[uid]+=p;
        sum[vid]+=p;

        adj[uid].emplace_back(v,-p);
        adj[vid].emplace_back(u,-p);

        adj[u].emplace_back(vid,0);
        adj[v].emplace_back(uid,0);
    }
    for (auto it:mid){
        int par=it.first.first;
        adj[par].emplace_back(it.second,0);
        for (pair<int,int>& jt:adj[it.second]){
            jt.second+=sum[it.second];
        }
    }
    priority_queue<pair<int,int>,vector<pair<int,int>>,greater<pair<int,int>>> q;
    vector<int> dis(n,1e18);
    dis[0]=0;
    q.emplace(0,0);
    while(!q.empty()){
        int w,u;
        tie(w,u)=q.top();
        q.pop();
        if (dis[u]!=w){continue;}
        for (pair<int,int>& it:adj[u]){
            if (dis[it.first]>it.second+w){
                dis[it.first]=w+it.second;
                q.emplace(dis[it.first],it.first);
            }
        }
    }
    cout<<(dis[gh-1]==1e18?-1:dis[gh-1]);
}

int32_t main(){
  ios::sync_with_stdio(false),cin.tie(nullptr),cout.tie(nullptr);
  int tq = 1;
  //cin>>tq;
  for (;tq--;){solve();}
}  

Compilation message (stderr)

Main.cpp: In function 'void solve()':
Main.cpp:21:9: warning: unused variable 'cur' [-Wunused-variable]
   21 |     int cur=n;
      |         ^~~

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