#include <bits/stdc++.h>
//#pragma GCC optimize("O3")
//#pragma GCC optimize("unroll-loops")
using namespace std;
#define int long long
#define vi vector<int>
#define vl vector<long long>
#define vii vector<pair<int,int>>
#define vll vector<pair<long long,long long>>
#define pb push_back
#define ll long long
#define ld long double
#define nl '\n'
#define boost ios::sync_with_stdio(false)
#define mp make_pair
#define se second
#define fi first
#define fore(i, y) for(int i = 0; i < y; i++)
#define forr(i,x,y) for(int i = x;i<=y;i++)
#define forn(i,y,x) for(int i = y; i >= x; i--)
#define all(v) v.begin(),v.end()
#define sz(v) (int)v.size()
#define clr(v,k) memset(v,k,sizeof(v))
#define rall(v) v.rbegin() , v.rend()
#define pii pair<int,int>
#define pll pair<ll , ll>
const ll MOD = 1e9 + 7;
const ll INF = 1e18 + 1;
ll gcd(ll a , ll b) {return b ? gcd(b , a % b) : a ;} // greatest common divisor (gcd)
ll lcm(ll a , ll b) {return a * (b / gcd(a , b));} // least common multiple (lcm)
// HERE IS THE SOLUTION
const int N = 1e5 + 10;
const int LOG = 20;
int n , s , q, e;
vii adj[N];
int mn[LOG][N] , par[LOG][N];
pii edges[N];
int depth[N];
int cost_closest[N];
int distE[N];
int Time = -1;
int tin[N] , tout[N];
void pre_dfs(int x , int p)
{
Time++;
tin[x] = Time;
for(auto [u , c] : adj[x])
{
if(u == p)
continue;
depth[u] = depth[x] + 1;
distE[u] = distE[x] + c;
pre_dfs(u , x);
cost_closest[x] = min(cost_closest[u] + c , cost_closest[x]);
}
tout[x] = Time;
}
void main_dfs(int x , int p)
{
for(auto [u , c] : adj[x])
{
if(u == p)
continue;
mn[0][u] = cost_closest[u] - distE[u];
par[0][u] = x;
forr(j , 1 , LOG - 1)
{
par[j][u] = par[j - 1][par[j - 1][u]];
mn[j][u] = min(mn[j - 1][u] , mn[j - 1][par[j - 1][u]]);
}
main_dfs(u , x);
}
}
bool is_ancestor(int anc , int node)
{
return (tin[node] <= tout[anc] && tin[node] >= tin[anc]);
}
signed main()
{
boost;
cin.tie(0);
cout.tie(0);
cin>>n>>s>>q>>e;
e--;
forr(i ,1, n - 1)
{
int u , v , c;
cin>>u>>v>>c;
u-- , v--;
adj[u].pb({v , c});
adj[v].pb({u , c});
edges[i] = { u , v};
}
fore(i , n)
cost_closest[i] = INF;
fore(i , s)
{
int x;
cin>>x;
x--;
cost_closest[x] = 0;
}
distE[e] = 0;
depth[e] = 0;
pre_dfs(e , -1);
main_dfs(e , -1);
while(q--)
{
int i , u;
cin>>i>>u;
u--;
int p = edges[i].first;
if(depth[edges[i].second] > depth[p])
p = edges[i].second;
if(is_ancestor(p , u))
{
int ans = cost_closest[u] - distE[u];
int node = u;
forn(j , LOG - 1 , 1)
{
int new_node = par[j - 1][node];
if(is_ancestor(p , new_node))
{
ans = min(ans , mn[j][node]);
node = new_node;
}
}
ans+=distE[u];
if(ans >= (int)1e16)
cout<<"oo"<<nl;
else
cout<<ans<<nl;
}
else
{
cout<<"escaped"<<nl;
}
}
}
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
14 ms |
39260 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
14 ms |
39260 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
175 ms |
45140 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
14 ms |
39260 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
