Submission #895571

#	Time	Username	Problem	Language	Result	Execution time	Memory
895571		vjudge1	Evacuation plan (IZhO18_plan)	C++17	0 / 100	146 ms	28500 KiB

plan

//#pragma comment(linker, "/stack:200000000")
//#pragma GCC optimize("Ofast")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
#include <map>
#include <set>
#include <list>
#include <cmath>
#include <ctime>
#include <deque>
#include <queue>
#include <stack>
#include <string>
#include <bitset>
#include <cstdio>
#include <limits>
#include <vector>
#include <climits>
#include <cstring>
#include <cstdlib>
#include <fstream>
#include <numeric>
#include <sstream>
#include <cassert>
#include <iomanip>
#include <iostream>
#include <algorithm>
#include <stdio.h>
#include <fstream>
#include <unordered_map>
using namespace std;

typedef long long ll;
typedef long double ld;

#define all(x) x.begin(),x.end()
#define pb push_back
#define ent "\n"

#define int long long

const int maxn = (int)2e5 + 13;
const ll inf = (long long)1e18 + 20;
const int mod = (int)1e9 + 7;

int n,m,k,q;
vector<pair<int,int>>g[maxn];
int a[maxn],b[maxn],c[maxn];
int dst[maxn];
int pr[maxn];
int sz[maxn];

int get(int x){
	if(x == pr[x])return x;
	return pr[x] = get(pr[x]);
}

void unite(int x,int y){
	x = get(x),y= get(y);
	if(x == y)return ;
	if(sz[x] > sz[y])swap(x,y);
	pr[x] = y;
	sz[y] += sz[x];
}

void solve(){
	cin >> n >> m ;
	for(int i = 1 ; i <= m ; i++){
		int x,y,w;cin >> x >> y >> w;
		g[x].pb({y,w});
		g[y].pb({x,w});
		a[i] = x,b[i] = y,c[i] = w;
	}
	cin >> k;
	set<pair<int,int>>s;
	for(int i = 1 ; i <= n ; i ++){
		dst[i] = inf;
		pr[i] = i;
	}
	for(int i = 1 ; i <= k ; i ++){
		int x;cin >> x;
		s.insert({0,x});
		dst[x] = 0;
	}
	while(s.size()){
		pair<int,int>v = *s.begin();
		s.erase(v);
		for(auto to : g[v.second]){
			int val = dst[v.second] + to.second;
			if(dst[to.first] > val){
				dst[to.first] = val;
				s.insert({val,to.first});
			}
		}
	}
	cin >> q;
	for(int i = 1 ; i <= q ; i ++){
		int x,y;cin >> x >> y;
		int l = 0,r = 1000,ans = 0;
		while(l <= r){
			int mid = (l + r) >> 1;
			for(int j = 1 ; j <= n ; j++){
				pr[j] = j;
                                  sz[j] = 1;
			}
			for(int j = 1 ; j <= m ; j ++){
				if(dst[a[j]] >= mid && dst[b[j]] >= mid){
					unite(a[j],b[j]);
				}
			}
			if(get(x)!=get(y))r = mid - 1;
			else l = mid + 1,ans = mid;
		}
		cout << ans << ent;
	}
}

signed main(){
	// freopen ("hps.in", "r", stdin);
	// freopen ("hps.out", "w", stdout);
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	int t = 1;
	//cin >> t;
	int test = 0;
	while(t --){
	//	cout << "Case " << ++test << ": ";
		solve();
	}
	return 0;
}

Compilation message (stderr)

plan.cpp: In function 'int main()':
plan.cpp:124:6: warning: unused variable 'test' [-Wunused-variable]
  124 |  int test = 0;
      |      ^~~~

• Subtask 1: 0 / 10
• Subtask 2: 0 / 13
• Subtask 3: 0 / 12
• Subtask 4: 0 / 19
• Subtask 5: 0 / 46