| # | Time | Username | Problem | Language | Result | Execution time | Memory |
|---|---|---|---|---|---|---|---|
| 75192 | kjp4155 | 경주 (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<bits/stdc++.h>
using namespace std;
#define VA_NUM_ARGS(...) VA_NUM_ARGS_IMPL_((0,__VA_ARGS__, 6,5,4,3,2,1))
#define VA_NUM_ARGS_IMPL_(tuple) VA_NUM_ARGS_IMPL tuple
#define VA_NUM_ARGS_IMPL(_0,_1,_2,_3,_4,_5,_6,N,...) N
#define macro_dispatcher(macro, ...) macro_dispatcher_(macro, VA_NUM_ARGS(__VA_ARGS__))
#define macro_dispatcher_(macro, nargs) macro_dispatcher__(macro, nargs)
#define macro_dispatcher__(macro, nargs) macro_dispatcher___(macro, nargs)
#define macro_dispatcher___(macro, nargs) macro ## nargs
#define Debug1(a) cout<<#a<<"="<<(a)<<"\n"
#define Debug2(a,b) cout<<#a<<"="<<(a)<<", "<<#b<<"="<<(b)<<"\n"
#define Debug3(a,b,c) cout<<#a<<"="<<(a)<<", "<<#b<<"="<<(b)<<", "<<#c<<"="<<(c)<<"\n"
#define Debug4(a,b,c,d) cout<<#a<<"="<<(a)<<", "<<#b<<"="<<(b)<<", "<<#c<<"="<<(c)<<", "<<#d<<"="<<(d)<<"\n"
#define Debug5(a,b,c,d,e) cout<<#a<<"="<<(a)<<", "<<#b<<"="<<(b)<<", "<<#c<<"="<<(c)<<", "<<#d<<"="<<(d)<<", "<<#e<<"="<<(e)<<"\n"
#define Debug6(a,b,c,d,e,f) cout<<#a<<"="<<(a)<<", "<<#b<<"="<<(b)<<", "<<#c<<"="<<(c)<<", "<<#d<<"="<<(d)<<", "<<#e<<"="<<(e)<<", "<<#f<<"="<<(f)<<"\n"
#define Debug(...) macro_dispatcher(Debug, __VA_ARGS__)(__VA_ARGS__)
#define DA(a,n) cout<<#a<<"=["; printarray(a,n); cout<<"]\n"
#define DAR(a,n,s) cout<<#a<<"["<<s<<"-"<<n-1<<"]=["; printarray(a,n,s); cout<<"]\n"
#define TT1 template<class T>
#define TT1T2 template<class T1, class T2>
#define TT1T2T3 template<class T1, class T2, class T3>
template<class T, size_t N> ostream& operator << (ostream& os, const array<T, N>& v);
TT1T2 ostream& operator << (ostream& os, const pair<T1, T2>& p){ return os <<"("<<p.first<<", "<< p.second<<")"; }
TT1 ostream& operator << (ostream& os, const vector<T>& v){ bool f=1;os<<"[";for(auto& i : v) { if (!f)os << ", ";os<<i;f=0;}return os << "]"; }
template<class T, size_t N> ostream& operator << (ostream& os, const array<T, N>& v) { bool f=1;os<<"[";for(auto& i : v) { if (!f)os << ", ";os<<i;f=0;}return os << "]"; }
TT1T2 ostream& operator << (ostream& os, const set<T1, T2>&v){ bool f=1;os<<"[";for(auto& i : v) { if (!f)os << ", ";os<<i;f=0;}return os << "]"; }
TT1T2 ostream& operator << (ostream& os, const multiset<T1,T2>&v){bool f=1;os<<"[";for(auto& i : v) { if (!f)os << ", ";os<<i;f=0;}return os << "]"; }
TT1T2T3 ostream& operator << (ostream& os, const map<T1,T2,T3>& v){ bool f = 1; os << "["; for (auto& ii : v) { if (!f)os << ", "; os << "(" << ii.first << " -> " << ii.second << ") "; f = 0; }return os << "]"; }
TT1T2 ostream& operator << (ostream& os, const multimap<T1, T2>& v){ bool f = 1; os << "["; for (auto& ii : v) { if (!f)os << ", "; os << "(" << ii.first << " -> " << ii.second << ") "; f = 0; }return os << "]"; }
TT1T2 ostream& operator << (ostream& os, priority_queue<T1, T2> v) { bool f = 1; os << "["; while (!v.empty()) { auto x = v.top(); v.pop(); if (!f) os << ", "; f = 0; os << x; } return os << "]"; }
TT1T2 void printarray(const T1& a, T2 sz, T2 beg = 0){ for (T2 i = beg; i<sz; i++) cout << a[i] << " "; cout << endl; }
typedef long long ll;
typedef unsigned long long ull;
typedef pair<int, int> Pi;
typedef pair<ll, ll> Pll;
#define Fi first
#define Se second
#define pb(x) push_back(x)
#define sz(x) (int)x.size()
#define rep(i, n) for(int i=0;i<n;i++)
#define repp(i, n) for(int i=1;i<=n;i++)
#define all(x) x.begin(), x.end()
#define geti1(X) cin >> X
#define geti2(X,Y) cin >> X >> Y
#define geti3(X,Y,Z) cin >> X >> Y >> Z
#define geti4(X,Y,Z,W) cin >> X >> Y >> Z >> W
#define GET_MACRO(_1,_2,_3,_4,NAME,...) NAME
#define geti(...) GET_MACRO(__VA_ARGS__, geti4, geti3, geti2, geti1) (__VA_ARGS__)
#define INF 987654321
#define endl '\n'
const ll mod = 1e9+7;
ll N,K;
vector<Pll> E[200500];
int sz[200500], mark[200500];
ll ans = 1e9;
ll mn_local[1000500], mn_global[1000500];
int dfs_build(int x, int p){
sz[x] = 1;
for(auto e : E[x])if(e.Fi!=p && !mark[e.Fi]){
sz[x] += dfs_build(e.Fi,x);
}
return sz[x];
}
int get_centroid(int x, int p, int total){
for(auto e : E[x])if(e.Fi!=p && !mark[e.Fi]){
if( sz[e.Fi] > total/2 ) return get_centroid(e.Fi,x,total);
}
return x;
}
vector<int> die_local, die_global;
void dfs(int x, int p, ll cnt, ll dist){
if( dist > K ) return;
mn_local[dist] = min(mn_local[dist], cnt);
die_local.push_back(dist);
die_global.push_back(dist);
for(auto e : E[x])if(e.Fi!=p && !mark[e.Fi]){
dfs(e.Fi,x,cnt+1,dist+e.Se);
}
}
void solve(int x){
dfs_build(x,-1);
int center = get_centroid(x,-1, sz[x]);
for(auto e : E[center]) if(!mark[e.Fi]){
// data for subtree e calculation phase
dfs(e.Fi,x,1,e.Se);
for(auto e : die_local){
if( e > K ) continue;
ans = min(ans, mn_local[e] + mn_global[K-e]);
}
// data for subtree e addition phase
for(auto e : die_local) mn_global[e] = min(mn_global[e], mn_local[e]);
for(auto e : die_local) mn_local[e] = 1e10;
die_local.clear();
}
for(auto e : die_global) mn_global[e] = 1e10;
die_global.clear();
mark[center] = 1;
for(auto e : E[center]) if(!mark[e.Fi]) solve(e.Fi);
}
int main(){
scanf("%lld%lld",&N,&K);
for(int i=1;i<=K;i++) mn_local[i] = mn_global[i] = 1e10;
repp(i,N-1){
ll a,b,c; scanf("%lld%lld%lld",&a,&b,&c);
E[a].push_back({b,c});
E[b].push_back({a,c});
}
solve(0);
if( ans >= 1e8 ) printf("-1\n");
else printf("%lld\n",ans);
}