# | Time | Username | Problem | Language | Result | Execution time | Memory |
---|---|---|---|---|---|---|---|
1000758 | nomuluun | Race (IOI11_race) | C++14 | 0 ms | 0 KiB |
This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
ll N, K;
ll H[200005][2];
ll L[200005];
bool vis[200005]={0};
vector<pair<int,int>>v[200005];
ll mi=INT_MAX;
void dfs(ll q, ll dis, ll hi){
int m=v[q].size();
if(dis==K){
mi=min(mi,hi);
}
for(int i=0; i<m; i++){
int k=v[q][i].first;
ll cost=v[q][i].second;
if(!vis[k]){
vis[k]=1;
dfs(k,dis+cost,hi+1);
}
}
}
int main(){
cin>>N>>K;
for(int i=0; i<N-1; i++){
cin>>H[i][0]>>H[i][1]>>L[i];
}
for(int i=0; i<N-1; i++){
v[H[i][0]].push_back({H[i][1], L[i]});
v[H[i][1]].push_back({H[i][0], L[i]});
}
for(int i=0; i<=N-1; i++){
for(int i=0; i<N; i++){
vis[i]=0;
}
vis[i]=1;
dfs(i,0,0);
}
if(mi==INT_MAX) cout<<-1;
else cout<<mi;
}