# | Time | Username | Problem | Language | Result | Execution time | Memory |
---|---|---|---|---|---|---|---|
412489 | jeqcho | Race (IOI11_race) | C++17 | 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 "grader.h"
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<int,int> pii;
typedef vector<int> vi;
typedef vector<pair<int,int>> vpi;
#define FOR(i,a,b) for (int i = (a); i < (b); ++i)
#define F0R(i,a) FOR(i,0,a)
#define ROF(i,a,b) for (int i = (b)-1; i >= (a); --i)
#define R0F(i,a) ROF(i,0,a)
#define trav(a,x) for (auto& a: x)
#define pb push_back
#define rsz resize
#define sz(x) int(x.size())
#define all(x) begin(x), end(x)
#define fi first
#define se second
int const n=2e5+3;
vpi adj[n];
int const INF=1e9;
// subtask 1,2
int dfs(int now, int par, int w, int k)
{
if(w > k)return INF;
if(w==k)return 0;
int mn=INF;
trav(chi,adj[now])
{
if(chi.fi==par)continue;
mn=min(mn,1+dfs(chi.fi,now,w+chi.se,k));
}
return mn;
}
int best_path(int N, int K, int H[][2], int L[]){
F0R(i,N-1)
{
int u = H[i][0];
int v = H[i][1];
adj[u].pb({v,L[i]});
adj[v].pb({u,L[i]});
}
int mn=INF;
F0R(i,N)
{
mn=min(mn,dfs(i,-1,0,K));
}
if(mn>=INF)return -1;
return mn;
}