Submission #772644

#	Time	Username	Problem	Language	Result	Execution time	Memory
772644		bgnbvnbv	Robot (JOI21_ho_t4)	C++14	100 / 100	135 ms	29508 KiB

Main

#include<bits/stdc++.h>
#define TASKNAME "codeforce"
#define pb push_back
#define pli pair<int,int>
#define fi first
#define se second
#define fastio ios_base::sync_with_stdio(false); cin.tie(NULL);
using namespace std;
using ll=long long;
#define int long long
const ll maxN=3e5;
const ll inf=1e18;
const ll mod=1e9+7;
ll n,m;
struct edge
{
    ll u,v,c,w;

}e[maxN];
// co 2 cach noi 1 la noi tu u->v
// 2 la tu 1 dinh ke cua u noi den u va tu u noi den v ( dinh ke va v cung mau )
vector<ll>g[maxN];
ll d[maxN];
priority_queue<pli,vector<pli>,greater<pli>>q;
ll mn[maxN],sum[maxN];
void solve()
{
    cin >> n >> m ;
    for(int i=1;i<=m;i++)
    {
        cin >> e[i].u >> e[i].v >> e[i].c >> e[i].w;
        g[e[i].u].pb(i);
        g[e[i].v].pb(i);
        mn[i]=inf;
        sum[i]=0;
    }
    q.push({0,1});
    d[1]=0;
    for(int i=2;i<=n;i++) d[i]=inf;
    while(!q.empty())
    {
        ll u=q.top().se;
        ll dis=q.top().fi;
        q.pop();
        if(dis>d[u]) continue;
        for(auto id:g[u])
        {
            int v=u^e[id].u^e[id].v;
            int w=e[id].w;
            int c=e[id].c;
            mn[c]=min(mn[c],d[v]);
            sum[c]+=w;
        }
        for(auto id:g[u])
        {
            int v=u^e[id].u^e[id].v;
            int w=e[id].w;
            int c=e[id].c;

            if(d[v]>d[u]+min(w,sum[c]-w))
            {
                d[v]=d[u]+min(w,sum[c]-w);
                q.push({d[v],v});
            }
            if(d[v]>mn[c]+sum[c]-w)
            {
                d[v]=mn[c]+sum[c]-w;
                q.push({d[v],v});
            }
            //if(v==3) cout << d[v]<<' '<<u<<' '<<mn[c]<<'\n';
            //if(v==2) cout <<d[v]<<' '<<u<<' '<<d[u]<<'\n';
        }
        for(auto id:g[u])
        {
            int v=u^e[id].u^e[id].v;
            int w=e[id].w;
            int c=e[id].c;
            mn[c]=inf;
            sum[c]=0;
        }
    }
    if(d[n]>=inf) cout << -1;
    else cout << d[n];
    //cout << '\n'<<d[2];
}
signed main()
{
    fastio
    //freopen(TASKNAME".INP","r",stdin);
    //freopen(TASKNAME".OUT","w",stdout);
    solve();
}

Compilation message (stderr)

Main.cpp: In function 'void solve()':
Main.cpp:75:17: warning: unused variable 'v' [-Wunused-variable]
   75 |             int v=u^e[id].u^e[id].v;
      |                 ^
Main.cpp:76:17: warning: unused variable 'w' [-Wunused-variable]
   76 |             int w=e[id].w;
      |                 ^

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