Submission #1098153

#	Time	Username	Problem	Language	Result	Execution time	Memory
1098153		vjudge1	Evacuation plan (IZhO18_plan)	C++17	41 / 100	4062 ms	32440 KiB

plan

#pragma GCC optimize("O3,unroll-loops")
#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")
#include<bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#define ll int
#define F first
#define S second
#define ull unsigned long long
#define db double
#define ldb long double
#define pb push_back
#define pf push_front
#define ppb pop_back
#define ppf pop_front
#define yes cout<<"YES\n"
#define no cout<<"NO\n"
#define ordered_set tree<ll,null_type,less<ll>,rb_tree_tag,tree_order_statistics_node_update>
#define all(x) x.begin(), x.end()

const int mod = 1e9 + 7;
const int N = 1e5 + 7;

using namespace std;
using namespace __gnu_pbds;

ll n, m, k, p[N], a, b, c, ans, d[N], l, r, used[N], res, mx;
set <pair <ll, ll>> s;
vector <pair <ll, ll>> g[N];

void dfs (ll v, ll md){
	if (d[v] < md){
		return;
	}
	if (c){
		return;
	}
	if (v == b){
		c = 1;
		return;
	}
	used[v] = 1;
	for (int i = 0; i < g[v].size(); i++){
		if (used[g[v][i].F] == 0 && d[g[v][i].F] >= md){
			dfs (g[v][i].F, md);
		}
	}
}

signed main (){
	ios_base::sync_with_stdio(0);
	cin.tie(0); cout.tie(0);
	cin >> n >> m;
	for (int i = 1; i <= m; i++){
		cin >> a >> b >> c;
		mx = max (mx, c);
		g[a].pb({b, c});
		g[b].pb ({a, c});
	}
	for (int i = 1; i <= n; i++){
		d[i] = 1e9;
	}
	cin >> k;
	for (int i = 1; i <= k; i++){
		cin >> p[i];
		d[p[i]] = 0;
	}
	for (int i = 1; i <= n; i++){
		s.insert({d[i], i});
	}
	while (s.size()){
		pair <ll, ll> opa = *s.begin();
		s.erase (opa);
		ll v = opa.second, w = opa.F;
		for (int i = 0; i < g[v].size(); i++){
			if (d[g[v][i].F] > w + g[v][i].S){
				s.erase ({d[g[v][i].F], g[v][i].F});
				d[g[v][i].F] = w + g[v][i].S;
				s.insert ({d[g[v][i].F], g[v][i].F});
			}
		}
	}
	cin >> k;
	while (k--){
		cin >> a >> b;
		l = 0, r = mx * n, res = 0;
		while (l <= r){
			ll md = (l + r) / 2;
			c = 0;
			for (int i = 1; i <= n; i++){
				used[i] = 0;
			}
//			cout << md << '\n';
			dfs (a, md);
//			cout << '\n';
			if (c){
				l = md + 1;
				res = md;
			}
			else{
				r = md - 1;
			}
		}
		cout << res << '\n';
	}
}
/*
9 12
1 9 4
1 2 5
2 3 7
2 4 3
4 3 6
3 6 4
8 7 10
6 7 5
5 8 1
9 5 7
5 4 12
6 8 2
2
4 7
5
1 6
5 3
4 8
5 8
1 5
*/

Compilation message (stderr)

plan.cpp: In function 'void dfs(int, int)':
plan.cpp:42:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   42 |  for (int i = 0; i < g[v].size(); i++){
      |                  ~~^~~~~~~~~~~~~
plan.cpp: In function 'int main()':
plan.cpp:74:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   74 |   for (int i = 0; i < g[v].size(); i++){
      |                   ~~^~~~~~~~~~~~~

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