Submission #49282

#	Time	Username	Problem	Language	Result	Execution time	Memory
49282		wzy	Factories (JOI14_factories)	C++11	0 / 100	6108 ms	232508 KiB

factories

#include <bits/stdc++.h>
#include "factories.h"
using namespace std;
#define pii pair<int,int>
#define F first
#define S second
#define pb push_back

vector<pii> adj[500005] , vt[500005];
int n , pai[500005] , lca[22][500005] , depth[500005] , st[500005] , t= 0 , ed[500005] ;
long long  dist[500005] , dp[2][500005];
bool fs[500005] , ss[500005];
void pre_dfs(int x , int y){
	pai[x] = y;
	st[x] = ++t;
	for(int j = 0 ; j < adj[x].size() ; j++){
		pii u = adj[x][j];
		if(u.first == y) continue;
		dist[u.first] = dist[x] + u.second;
		depth[u.first] = depth[x] + 1;
		pre_dfs(u.first, x);
	}
	ed[x] = t;
}

int query_lca(int x , int y){
	if(depth[x] > depth[y]) swap(x,y);
	for(int j = 21 ; j >= 0 ; j--){
		int u = depth[y] - (1<<j);
		if(u >= depth[x]){
			y = lca[j][y];
		}
	}
	if(x == y) return x;
	for(int j = 21 ; j >= 0 ; j--){
		if(lca[j][x] != lca[j][y] && lca[j][x] != -1){
			x = lca[j][x] , y = lca[j][y];
		}
	}
	return pai[x];
}

long long distance_query(int x , int y){
	return dist[x] + dist[y] - 2*dist[query_lca(x,y)];
}


void Init(int N, int A[], int B[], int D[]){
	n = N;
	for(int i = 0 ; i < N - 1 ; i++){
		adj[A[i]].pb(pii(B[i] , D[i]));
		adj[B[i]].pb(pii(A[i] , D[i]));
	}
	depth[0] = 0 , dist[0] = 0;
	pre_dfs(0 , - 1 );
	for(int i = 0 ; i < N ; i++){
		lca[0][i] = pai[i];
	}
	for(int j = 1 ; j < 22 ; j++){
		for(int i = 0 ; i < N ; i++){
			lca[j][i] = lca[j-1][lca[j-1][i]];
		}
	}
}

bool cmp(pii a , pii b){
	if(st[a.F] == st[b.F]) return a.S < b.S;
	return st[a.F] < st[b.F];
}

long long ansz = 0;

void solve(int x , int y){
	for(int j = 0 ; j <vt[x].size() ; j++){
		pii u = vt[x][j];
		if(u.first == y) continue;
		solve(u.first , x);
			dp[0][x] = min(dp[0][x] , u.second + dp[0][u.first]);
			dp[1][x] = min(dp[1][x] , u.second + dp[1][u.first]);
	}
	long long maxA = (long long) 1e18 , maxB = (long long) 1e18;
	if(fs[x]) maxA = 0;
	if(ss[x]) maxB = 0;
	for(int j = 0 ; j < vt[x].size() ; j++){
		pii u = vt[x][j];
		if(u.first == y) continue;
		ansz = min(ansz , dp[0][u.first] + maxB + u.second);
		ansz = min(ansz , dp[1][u.first] + maxA + u.second);
		maxA = min(maxA , dp[0][u.first] + u.second);
		maxB = min(maxB , dp[1][u.first] + u.second);
	}
	if(fs[x])  ansz = min(ansz , dp[1][x]);
	if(ss[x])  ansz = min(ansz , dp[0][x]);
	return ;
}

long long Query(int S , int X[] , int T , int Y[]){
	vector<pii> v;
	for(int i = 0 ; i < S ;i ++){
		v.pb(pii(X[i] , 0));
	}
	for(int i = 0 ; i < T ;i ++){
		v.pb(pii(Y[i] , 1));
	}
	sort(v.begin() , v.end() , cmp);
	vector<pii> op;
	set<int> u;
	for(int i = 0 ; i < v.size() ; i++){
		if(!u.count(v[i].F)){
			op.push_back(v[i]);
			u.insert(v[i].F);
		}
	}
	for(int i = 0 ; i < ((int)v.size()) - 1 ; i++){
		if(!u.count(query_lca(v[i].F , v[i+1].F))){
		op.push_back(pii(query_lca(v[i].F , v[i+1].F) , 3));
		u.insert(query_lca(v[i].F , v[i+1].F));
		}
	}
	sort(op.begin() , op.end() ,cmp);
	for(int i = 0 ; i < op.size() ; i++){
		if(op[i].second == 0){
			fs[op[i].first] = 1;
		}
		else if(op[i].second == 1){
			ss[op[i].first] =  1 ;
		}
	}
	stack<int> w;
	int root = 0;
	for(int i = 0 ; i < op.size() ; i++){
		dp[0][op[i].first] = (long long) 1e18;
		dp[1][op[i].first] = (long long) 1e18;
		if(w.empty()) w.push(op[i].first) , root = op[i].first;
		else{
			while(w.size() && !(st[w.top()] <= st[op[i].first] && st[op[i].first] <= ed[w.top()])){
				w.pop();
			}
			vt[op[i].first].push_back(pii(w.top() , distance_query(w.top() , op[i].first)));
			vt[w.top()].push_back(pii(op[i].first , distance_query(w.top() , op[i].first)));
			w.push(op[i].first);
		}
	}
	for(int i = 0 ; i < op.size() ; i++){
		if(fs[op[i].first]) dp[0][op[i].first] = 0;
		if(ss[op[i].first]) dp[1][op[i].first] = 0;
	}
	ansz = (long long) 1e18;
	solve(root , root);
	for(int i = 0 ; i < op.size() ; i++){
		vt[op[i].first].clear();
		if(op[i].second == 0){
			fs[op[i].first] = 0;
		}
		else if(op[i].second == 1){
			ss[op[i].first] =  0 ;
		}
	}
	return ansz;
}

Compilation message (stderr)

factories.cpp: In function 'void pre_dfs(int, int)':
factories.cpp:16:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int j = 0 ; j < adj[x].size() ; j++){
                  ~~^~~~~~~~~~~~~~~
factories.cpp: In function 'void solve(int, int)':
factories.cpp:74:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int j = 0 ; j <vt[x].size() ; j++){
                  ~~^~~~~~~~~~~~~
factories.cpp:84:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int j = 0 ; j < vt[x].size() ; j++){
                  ~~^~~~~~~~~~~~~~
factories.cpp: In function 'long long int Query(int, int*, int, int*)':
factories.cpp:108:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i = 0 ; i < v.size() ; i++){
                  ~~^~~~~~~~~~
factories.cpp:121:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i = 0 ; i < op.size() ; i++){
                  ~~^~~~~~~~~~~
factories.cpp:131:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i = 0 ; i < op.size() ; i++){
                  ~~^~~~~~~~~~~
factories.cpp:144:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i = 0 ; i < op.size() ; i++){
                  ~~^~~~~~~~~~~
factories.cpp:150:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i = 0 ; i < op.size() ; i++){
                  ~~^~~~~~~~~~~

• Subtask 1: 0 / 15
• Subtask 2: 0 / 18
• Subtask 3: 0 / 67