Submission #496469

#	Time	Username	Problem	Language	Result	Execution time	Memory
496469		mansur	Valley (BOI19_valley)	C++14	100 / 100	199 ms	72176 KiB

valley

#include<bits/stdc++.h>	
 
#pragma optimize ("g",on)
#pragma GCC optimize ("inline")
#pragma GCC optimize ("Ofast")
#pragma GCC optimize ("unroll-loops")
#pragma GCC optimize ("03")
#pragma GCC target ("sse,sse2,sse3,ssse3,sse4,popcnt,abm,avx2,mmx,fma,avx,tune=native")
#pragma comment(linker, "/stack:200000000")
 
//01001101 01100001 01101011 01101000 01100001  01100111 01100001 01111001 
 
using namespace std;
 
#define all(a) a.begin(), a.end()                                                   
#define rall(a) a.rbegin(), a.rend()
#define ll long long
#define pb push_back
#define sz(a) a.size()
#define nl '\n'
#define popb pop_back()                                                                   
#define ld double
#define ull unsigned long long
#define ff first                                         
#define ss second  
#define fix fixed << setprecision
#define pii pair<int, int>                          
#define E exit (0)
#define int long long
 
const int inf = 1e15, N = 1e6 + 1, mod = 998244353;                    
 
vector<pii> dir = {{1, 0}, {0, 1}, {-1, 0}, {0, -1}};
 
vector<pii> adj[N];
 
int tin[N], tout[N], timer;

pii up[N][20];       

int dist[N], iss[N], dp[N];
 
void dfs(int u, int p) {
	tin[u] = timer++;
	dp[u] = inf;
	if (iss[u]) dp[u] = 0;
	for (auto e: adj[u]) {
		if (e.ff != p) {
			dist[e.ff] = dist[u] + e.ss;
			dfs(e.ff, u);
			dp[u] = min(dp[u], dp[e.ff] + e.ss);
		}
	}
	tout[u] = timer++;	
}

void calc(int u, int p) {
	up[u][0] = {p, min(dp[u] - dist[u], dp[p] - dist[p])};
	for (int i = 1; i < 18; i++) {
		up[u][i] = {up[up[u][i - 1].ff][i - 1].ff, min(up[u][i - 1].ss, up[up[u][i - 1].ff][i - 1].ss)};
	}
	for (auto e: adj[u]) {
		if (e.ff != p) {
			calc(e.ff, u);
		}
	}
}
 
bool is(int a, int b) {
	return tin[a] <= tin[b] && tout[a] >= tout[b];
}

int get(int a, int b) {
	if (a == b) return dp[a] - dist[a];
	int ans = inf;
	for (int i = 17; i >= 0; i--) {
    	pii x = up[a][i];
    	if (is(x.ff, b)) continue;
    	ans = min(ans, x.ss); 
    	a = x.ff;
    }
    return min(ans, up[a][0].ss);
}
 
main() {                                                         
	//freopen("cowrect.in", "r", stdin);                                                                                     
	//freopen("cowrect.out", "w", stdout);                                                                                     
	ios_base::sync_with_stdio(NULL);                                                                                        
	cin.tie(NULL);
	int n, st, q, e;
	cin >> n >> st >> q >> e;
	int u[n], v[n], w[n];
	for (int i = 1; i < n; i++) {
		cin >> u[i] >> v[i] >> w[i];
		adj[u[i]].pb({v[i], w[i]});
		adj[v[i]].pb({u[i], w[i]});
	}                 
	for (int i = 1, c; i <= st; i++) {
		cin >> c;
		iss[c] = 1;
	}
	dfs(e, e);
	calc(e, e);    
	while (q--) {
		int i, x;
		cin >> i >> x;
		if (is(v[i], u[i])) swap(u[i], v[i]);
		if (is(v[i], x)) {
			if (dp[v[i]] == inf) {
				cout << "oo" << nl;
				continue;
			}
			cout << min(dp[x], get(x, v[i]) + dist[x]) << nl;
		}else {
			cout << "escaped" << nl;
		}
	}
}

Compilation message (stderr)

valley.cpp:3: warning: ignoring '#pragma optimize ' [-Wunknown-pragmas]
    3 | #pragma optimize ("g",on)
      | 
valley.cpp:9: warning: ignoring '#pragma comment ' [-Wunknown-pragmas]
    9 | #pragma comment(linker, "/stack:200000000")
      | 
valley.cpp:85:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   85 | main() {
      | ^~~~

• Subtask 1: 9 / 9
• Subtask 2: 27 / 27
• Subtask 3: 23 / 23
• Subtask 4: 41 / 41