Submission #964606

#	Time	Username	Problem	Language	Result	Execution time	Memory
964606		onebit1024	Olympic Bus (JOI20_ho_t4)	C++17	5 / 100	1079 ms	6476 KiB

ho_t4

#include <bits/stdc++.h>
using namespace std;

#define int long long
#define pb push_back
#define all(c) c.begin(), c.end()
#define endl "\n"

const double PI=3.141592653589;


void __print(int x) {cerr << x;}
void __print(long x) {cerr << x;}
void __print(unsigned x) {cerr << x;}
void __print(unsigned long x) {cerr << x;}
void __print(unsigned long long x) {cerr << x;}
void __print(float x) {cerr << x;}
void __print(double x) {cerr << x;}
void __print(long double x) {cerr << x;}
void __print(char x) {cerr << '\'' << x << '\'';}
void __print(const char *x) {cerr << '\"' << x << '\"';}
void __print(const string &x) {cerr << '\"' << x << '\"';}
void __print(bool x) {cerr << (x ? "true" : "false");}

template<typename T, typename V>
void __print(const pair<T, V> &x) {cerr << '{'; __print(x.first); cerr << ','; __print(x.second); cerr << '}';}
template<typename T>
void __print(const T &x) {int f = 0; cerr << '{'; for (auto &i: x) cerr << (f++ ? "," : ""), __print(i); cerr << "}";}
void _print() {cerr << "]\n";}
template <typename T, typename... V>
void _print(T t, V... v) {__print(t); if (sizeof...(v)) cerr << ", "; _print(v...);}
#ifndef ONLINE_JUDGE
#define dbg(x...) cerr << "LINE(" << __LINE__ << ") -> " <<"[" << #x << "] = ["; _print(x)
#else
#define dbg(x...)
#endif

int n,m;
vector<set<pair<int,int>>>adj;
const int inf = 1e18;
int dij(int u, int v){
    vector<int>dist(n+1,inf);
    dist[u] = 0;
    priority_queue<pair<int,int>,vector<pair<int,int>>,greater<pair<int,int>>>pq;
    pq.push({0,u});
    while(!pq.empty()){
        int u = pq.top().second, d = pq.top().first;
        pq.pop();
        if(d!=dist[u])continue;
        for(auto &[v,c] : adj[u]){
            if(dist[u] +c < dist[v]){
                dist[v] = dist[u]+c;
                pq.push({dist[v],v});
            }
        }
    }
    return dist[v];
}

void solve()
{
    cin >> n >> m;
    adj = vector<set<pair<int,int>>>(n+1);
    vector<vector<int>>edges;
    for(int i = 1;i<=m;++i){
        int u,v,c,d;cin >> u >> v >> c >> d;
        adj[u].insert({v,c});
        edges.pb({u,v,c,d});
    }

    int res = min(inf,dij(1,n)+dij(n,1));
    for(auto x : edges){
        int u = x[0], v = x[1], c = x[2], d = x[3];
        adj[u].erase({v,c});
        adj[v].insert({u,c});
        res = min(res, dij(1,n) + dij(n,1)+d);
        adj[u].insert({v,c});
        adj[v].erase({u,c});
    }
    if(res==inf)res = -1;
    cout << res << endl;
}   

int32_t main()
{

    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);


    // freopen("input.txt", "r", stdin);
    // freopen("output.txt", "w", stdout);
    

    int T=1;
    for(int i = 1;i<=T;++i)
    {
        // cout << "Case #" << i << ": ";
        solve();
    }
}

• Subtask 1: 5 / 5
• Subtask 2: 0 / 11
• Subtask 3: 0 / 21
• Subtask 4: 0 / 63