Submission #950597

#	Time	Username	Problem	Language	Result	Execution time	Memory
950597		Nexus	Two Currencies (JOI23_currencies)	C++17	10 / 100	159 ms	192964 KiB

currencies

#include <bits/stdc++.h>
#define ll long long

using namespace std;

const ll N=2e3+9,M=2e18+9,mod=1e9+7;

ll a[N],b[N],n,m,q,s,t,x,y,z;
vector<ll>v[N],ed[N][N],p;

void dfs(ll node,ll ca)
{
    if(node==t)
    {
        z=1;
        return;
    }
    for(auto i:v[node])
    if(i!=ca)
    {
        ll g=p.size();
        for(auto j:ed[node][i])p.push_back(j);
        dfs(i,node);
        if(z)return;
        ll k=g+ed[node][i].size();
        for(ll j=g;j<k;++j)p[j]=0;
    }
}

ll ans()
{
    p.clear();
    z=0;
    dfs(s,s);
    
    sort(p.begin(),p.end());
    n=p.size();
    for(ll i=0;i<n;++i)
    {
        if(p[i]<=y)y-=p[i];
        else
        {
            x-=p.size()-i;
            break;
        }
    }
    
    if(x>=0)return x;
    return -1;
    
}

int main()
{
    ios::sync_with_stdio(0);
    cin.tie(0);cout.tie(0);
    
    cin>>n>>m>>q;
    for(ll i=1;i<n;++i)
    {
        cin>>a[i]>>b[i];
        v[a[i]].push_back(b[i]);
        v[b[i]].push_back(a[i]);
    }
    
    for(ll i=0;i<m;++i)
    {
        cin>>x>>y;
        ed[a[x]][b[x]].push_back(y);
        ed[b[x]][a[x]].push_back(y);
    }
    
    while(q--)
    {
        cin>>s>>t>>x>>y;
        cout<<ans()<<'\n';
    }
    
    return 0;
}

• Subtask 1: 10 / 10
• Subtask 2: 0 / 28
• Subtask 3: 0 / 30
• Subtask 4: 0 / 32