Submission #805676

#	Time	Username	Problem	Language	Result	Execution time	Memory
805676		shadow_sami	Race (IOI11_race)	C++17	100 / 100	309 ms	84764 KiB

race

#include "race.h"
#include<bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
using namespace std;
typedef long long int ll;
typedef vector<ll> vi;
typedef vector<vector<ll>> vvi;
typedef pair<ll,ll> pi;
typedef map<ll,ll> mi;
typedef long double ld;
typedef vector<ld> vd;
typedef vector<vector<ld>> vvd;
typedef pair<ld,ld> pd;
#define ff first
#define ss second
#define srt(a) sort(a.begin(),a.end());
#define fip(k, n) for (ll i = k; i < n; i++)
#define fjp(k, n) for (ll j = k; j < n; j++)
#define fin(k, n) for (ll i = k; i >= n; i--)
#define fjn(k, n) for (ll j = k; j >= n; j--)
#define fp(k, n, m) for (ll k = n; k < m; k++)
#define fn(k, n, m) for (ll k = n; k >= m; k--)
#define ordered_set tree<pi, null_type,less< pi >, rb_tree_tag,tree_order_statistics_node_update>
#define totalOne(n) __builtin_popcount(n)
#define backZero(n) __builtin_ctzll(n)
#define frontZero(n) __builtin_clzll(n)
#define fx(k) for ( auto x : k )
#define test ll t;cin >> t;while (t--)
#define nli "\n"

// ==========================(debug)============================================================================================== //

#ifndef ONLINE_JUDGE
#define debug(x) cerr << #x <<" "; _printn(x); cerr << nli;
#else
#define debug(x)
#endif

void _printn(ll x){ cerr<<x<<" "; }
void _printn(int x){ cerr<<x<<" "; }
void _printn(ld x){ cerr<<x<<" "; }
void _printn(double x){ cerr<<x<<" "; }
void _printn(string x){ cerr<<x<<" "; }
void _printn(char x){ cerr<<x<<" "; }
void _printn(bool x){ cerr<<x<<" "; }
template<class T,class V>void _printn(pair<T,V> vv);
template<class T> void _printn(vector<T> vv);
template<class T> void _printn(set<T> vv);
template<class T,class V> void _printn(map<T,V> vv);
template<class T> void _printn(multiset<T> vv);
template<class T,class V>void _printn(pair<T,V> vv){ cerr<<"( ";_printn(vv.ff);cerr<<",";_printn(vv.ss);cerr<<")";}
template<class T> void _printn(vector<T> vv){ cerr<<"[ "; for(auto xx:vv){ _printn(xx);cerr<<" "; } cerr<<"]"; };
template<class T> void _printn(set<T> vv){ cerr<<"{ "; for(auto xx:vv){ _printn(xx);cerr<<" "; } cerr<<"}"; };
template<class T> void _printn(multiset<T> vv){ cerr<<"{ "; for(auto xx:vv){ _printn(xx);cerr<<" "; } cerr<<"}"; };
template<class T,class V> void _printn(map<T,V> vv){ cerr<<"{ "; for(auto xx:vv){ _printn(xx);cerr<<" "; } cerr<<"}"; };

// ==========================(debug)============================================================================================== //

ll n,m,tp,tp2,res,cnt,sum,tptp,ans;
const ll mx = 5e5+5;
const ll mod = 1e9+7;

// ==========================(MOD)=============================================================================================== //

ll mod_add(ll aa,ll bb){ return ((aa%mod)+(bb%mod))%mod; }
ll mod_minus(ll aa,ll bb){ return (((aa%mod)-(bb%mod))+10*mod)%mod; }
ll mod_mul(ll aa,ll bb){ return ((aa%mod)*(bb%mod))%mod; }
ll mod_power(ll aa,ll bb){ aa%=mod; ll empowered = 1; bb%=mod-1; while(bb > 0){ if(bb & 1) empowered = mod_mul(empowered,aa); bb = bb >> 1; aa = mod_mul(aa,aa); } return empowered; }
ll mod_divi(ll aa,ll bb){ aa=mod_mul(aa,mod_power(bb,mod-2)); return aa; }

// ==========================(MOD)=============================================================================================== //

bool f = false;
set<pi> st[mx];
vector<pi> adj[mx];
ll dep[mx];
ll dis[mx];
int sr,de;

void merge(ll a,ll b){
	if(st[a].size() < st[b].size())
		st[a].swap(st[b]);
	res = m + 2*dis[a];
	fx(st[b]){
		if(st[a].lower_bound({res - x.ff,0}) == st[a].end())
			continue;
		auto it = st[a].lower_bound({res - x.ff,0});
		if(res-x.ff!=it->ff)
			continue;
		ans = min(ans,it->ss+x.ss - 2*dep[a]);
	}
	fx(st[b])
		st[a].insert(x);
	st[b].clear();
	return;
}

void dfs(ll u,ll par){
	fx(adj[u])
		if(x.ff!=par){
			dis[x.ff] = dis[u] + x.ss;
			dep[x.ff] = dep[u] + 1;
			dfs(x.ff,u);
			merge(u,x.ff);
		}		
	tp = m + dis[u];
	if(st[u].lower_bound({tp,0}) != st[u].end()){
		auto it = st[u].lower_bound({tp,0});
		if(tp==it->ff)
			ans = min(ans,it->ss - dep[u]);
	}
	st[u].insert({dis[u],dep[u]});	
	return;	
}

int best_path(int N, int K, int H[][2], int L[]){
	ans = 1e18;
	n = N;
	m = K;	
	fip(0,n-1){
		sr = H[i][0];
		de = H[i][1];
		tp = L[i];
		adj[sr].push_back({de,tp});
		adj[de].push_back({sr,tp});
	}
	dep[0] = 0;
	dis[0] = 0;
	dfs(0,-1);
	if(ans==1e18)
		ans = -1;
	return ans;
}

// int main(){
//     ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);
//     #ifndef ONLINE_JUDGE
//         freopen("input1.txt", "r", stdin);
//         freopen("output1.txt", "w", stdout);
//         freopen("error1.txt", "w", stderr);
//     #endif // ONLINE_JUDGE

//         ll N,K;
//         cin>>N>>K;
//         int H[N-1][2];
//         int L[N-1];
//         fip(0,N-1)
//         	cin>>H[i][0]>>H[i][1]>>L[i];
//         cout<<best_path(N,K,H,L)<<nli;
        
//     cerr << "Time elapsed: " << setprecision(6) << 1000.0 * clock() / CLOCKS_PER_SEC << "ms\n";
//     return 0;
// }

• Subtask 1: 9 / 9
• Subtask 2: 12 / 12
• Subtask 3: 22 / 22
• Subtask 4: 57 / 57