Submission #379035

#	Time	Username	Problem	Language	Result	Execution time	Memory
379035		Kalashnikov	Evacuation plan (IZhO18_plan)	C++17	100 / 100	2567 ms	32052 KiB

plan

#include <bits/stdc++.h>
 
#define ios ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0)
#define file(s) if (fopen(s".in", "r")) freopen(s".in", "r", stdin), freopen(s".out", "w", stdout)
#define all(a) a.begin() , a.end()
#define F first
#define S second
 
using namespace std;
using ll = long long;
 
const int N = 2e5+5 , inf = 2e9 + 7;
const ll INF = 1e18 ,   mod = 1e9+7 , P = 6547;

vector<pair<int,int>> g[N];
int bad[N];
int d[N];
int s[N] , t[N] , l[N] , r[N] , p[N] , sz[N] , ans[N] , u[N];

int get(int v) {
	if(v == p[v]) return v;
	return p[v] = get(p[v]);
}

void merge(int a , int b) {
	a = get(a);
	b = get(b);
	if(a == b) return;
	if(sz[a] < sz[b]) swap(a , b);
	sz[a] += sz[b];
	p[b] = a; 
}

void solve() {
	int n , m;
	cin >> n >> m;
	for(int i = 1; i <= m; i ++) {
		int a , b,  c;
		cin >> a >> b >> c;
		g[a].push_back({b , c});
		g[b].push_back({a , c});
	}
	for(int i = 1; i <= n; i ++) {
		d[i] = inf;
	}
	
	set<pair<int,int>> dij;
	int k;
	cin >> k;
	for(int i = 1; i <= k; i ++) {
		int x;
		cin >> x;
		bad[x] = 1;
		d[x] = 0;		
		dij.insert({d[x] , x});
	}
	
	while(dij.size()) {
		pair<int,int> cur = *dij.begin();
		dij.erase(cur);
		for(auto to: g[cur.S]) {
			if(cur.F + to.S < d[to.F]) {
				d[to.F] = cur.F + to.S;
				dij.insert({d[to.F] , to.F});
			}
		}
	}
	
	int q;
	cin >> q;
	for(int i = 1; i <= q; i ++) {
		cin >> s[i] >> t[i];
		if(bad[s[i]] || bad[t[i]]) {
			ans[i] = 0;
			l[i] = 1;
			continue;
		}
		else {
			l[i] = 0 , r[i] = (int)(1e9);
		}
	}
	
	for(int JUMBL = 0; JUMBL < 30; JUMBL ++) {
		vector<pair<int,int>> events;
		for(int i = 1; i <= q; i ++) {
			if(l[i] <= r[i]) {
				int md = l[i]+r[i] >> 1;
				events.push_back({md , -i});
			}
		}
		if(events.empty()) continue;
		for(int i = 1; i <= n; i ++) {
			events.push_back({d[i] , i});
			u[i] = 0;
			p[i] = i;
			sz[i] = 1;
		}
		
		sort(all(events));
		reverse(all(events));
		for(auto to: events) {
			int x = to.F , i = to.S;
			if(i > 0) {
				//i = -i;
				u[i] = 1;
				for(auto to: g[i]) {
					if(u[to.F] == 1) {
						merge(i , to.F);
					}
				}
			}
			else {
				i = -i;
				if(get(s[i]) == get(t[i])) {
					ans[i] = x;
					l[i] = x+1;
				}
				else {
					r[i] = x-1;
				}
			}
		}
	}
	for(int i = 1; i <= q; i ++) {
		cout << ans[i] << '\n';
	}
}
/*
*/
main() {
    ios;
    int tt = 1;
    //cin >> tt;
    while(tt --) {
        solve();
    }
    return 0;
}

Compilation message (stderr)

plan.cpp: In function 'void solve()':
plan.cpp:87:18: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   87 |     int md = l[i]+r[i] >> 1;
      |              ~~~~^~~~~
plan.cpp: At global scope:
plan.cpp:130:6: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
  130 | main() {
      |      ^

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