oj.uz

Submission #256345

# Submission time Handle Problem Language Result Execution time Memory
256345 2020-08-02T14:59:01 Z AmineWeslati Valley (BOI19_valley) C++14
100 / 100
 432 ms 71416 KB 
//Never stop trying
#pragma GCC optimize("O3")
#include <bits/stdc++.h>
using namespace std;
#define boost ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0)

typedef string str;
typedef long long ll;
#define int ll
typedef double db;
typedef long double ld;

typedef pair<int,int> pi;
#define fi first
#define se second

typedef vector<int> vi;
typedef vector<ld> vd;
typedef vector<str> vs;
typedef vector<pi> vpi;

#define pb push_back
#define eb emplace_back
#define pf push_front

#define lb lower_bound
#define ub upper_bound

#define sz(x) (int)x.size()
#define all(x) begin(x), end(x)
#define rall(x) rbegin(x), rend(x)
#define endl "\n"

const int MOD = 1e9+7; //998244353
const ll INF = 1e18;
const int nx[4]={0,0,1,-1}, ny[4]={1,-1,0,0}; //right left down up

void IO(){
#ifndef ONLINE_JUDGE 
    freopen("input.txt", "r", stdin); 
    freopen("output.txt", "w", stdout); 
#endif 
}

const int MX=1e5+10;

int N,S,Q,E;
pi edges[MX];
vpi adj[MX];
bool shop[MX]={false};

int lvl[MX],tin[MX],tout[MX];
int timer;

int distE[MX],closest[MX],magic[MX];

int jump[MX][32],jumpMagic[MX][32];

void dfs(int u, int p, int l){
	tin[u]=timer++;
	lvl[u]=l;
	for(auto v: adj[u]) if(v.fi!=p){distE[v.fi]=distE[u]+v.se; dfs(v.fi,u,l+1);}
	tout[u]=timer++;
}

void dfs2(int u, int p){
   for(auto v: adj[u]) if(v.fi!=p) dfs2(v.fi,u);
	int ans=INF;
	if(shop[u]) ans=distE[u];
   for(auto v: adj[u]) if(v.fi!=p) ans=min(ans,closest[v.fi]);
	closest[u]=ans;
}

void build(int u, int p){
	jump[u][0]=p;
	for(int i=1; i<32; i++) jump[u][i]=jump[jump[u][i-1]][i-1];

	jumpMagic[u][0]=magic[u];
	for(int i=1; i<32; i++) jumpMagic[u][i]=min(jumpMagic[u][i-1],jumpMagic[jump[u][i-1]][i-1]);

	for(auto v: adj[u])if(v.fi!=p) build(v.fi,u);
}

bool ancestor(int u, int v){
	if(tin[v]>=tin[u] && tout[v]<=tout[u]) return true;
	else return false;
}

int32_t main(){
   boost;
   //IO();

   cin>>N>>S>>Q>>E;
   for(int i=0; i<N-1;i++){
   	int u,v,w; cin>>u>>v>>w;
   	edges[i]={u,v};
   	adj[u].pb({v,w});
   	adj[v].pb({u,w});
   }
   for(int i=0; i<S; i++){
   	int x; cin>>x; shop[x]=true;
   }

   timer=0; distE[E]=0;
   dfs(E,E,1);
   //for(int i=1; i<=N; i++) cout << distE[i] << ' '; cout << endl;
   dfs2(E,E);
   //for(int i=1; i<=N; i++) cout << closest[i] << ' '; cout << endl;
   for(int u=1; u<=N; u++) magic[u]=-2*distE[u]+closest[u];
   //for(int i=1; i<=N; i++) cout << magic[i] << ' '; cout << endl;

   build(E,E);

   while(Q--){
   	int idx,R; cin>>idx>>R; idx--;
   	int u=edges[idx].fi; if(lvl[edges[idx].se]>lvl[edges[idx].fi]) u=edges[idx].se;

   	if(!ancestor(u,R)) cout << "escaped" << endl;
   	else{
         int ans=INF;
         int d=distE[R];
         for(int i=31; i>=0; i--) if(ancestor(u,jump[R][i])) ans=min(ans,jumpMagic[R][i]), R=jump[R][i];
         ans=min(ans,magic[u]);
         if(ans>=(1e15)) cout << "oo" << endl;
         else cout << ans+d << endl;
      }
   }


	

   return 0;
}

Compilation message

valley.cpp: In function 'void IO()':
valley.cpp:40:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
     freopen("input.txt", "r", stdin); 
     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
valley.cpp:41:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
     freopen("output.txt", "w", stdout); 
     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
9.0 / 9.0

# Verdict Execution time Memory Grader output
1 Correct 5 ms 2944 KB Output is correct
2 Correct 4 ms 2944 KB Output is correct
3 Correct 4 ms 3072 KB Output is correct
4 Correct 4 ms 2944 KB Output is correct

Subtask #2
27.0 / 27.0

# Verdict Execution time Memory Grader output
1 Correct 5 ms 2944 KB Output is correct
2 Correct 4 ms 2944 KB Output is correct
3 Correct 4 ms 3072 KB Output is correct
4 Correct 4 ms 2944 KB Output is correct
5 Correct 4 ms 3456 KB Output is correct
6 Correct 3 ms 3456 KB Output is correct
7 Correct 3 ms 3456 KB Output is correct
8 Correct 4 ms 3456 KB Output is correct
9 Correct 4 ms 3456 KB Output is correct
10 Correct 3 ms 3456 KB Output is correct
11 Correct 3 ms 3456 KB Output is correct
12 Correct 4 ms 3456 KB Output is correct
13 Correct 3 ms 3456 KB Output is correct
14 Correct 4 ms 3456 KB Output is correct

Subtask #3
23.0 / 23.0

# Verdict Execution time Memory Grader output
1 Correct 209 ms 68856 KB Output is correct
2 Correct 221 ms 68600 KB Output is correct
3 Correct 252 ms 68984 KB Output is correct
4 Correct 280 ms 69880 KB Output is correct
5 Correct 250 ms 70136 KB Output is correct
6 Correct 432 ms 71160 KB Output is correct

Subtask #4
41.0 / 41.0

# Verdict Execution time Memory Grader output
1 Correct 5 ms 2944 KB Output is correct
2 Correct 4 ms 2944 KB Output is correct
3 Correct 4 ms 3072 KB Output is correct
4 Correct 4 ms 2944 KB Output is correct
5 Correct 4 ms 3456 KB Output is correct
6 Correct 3 ms 3456 KB Output is correct
7 Correct 3 ms 3456 KB Output is correct
8 Correct 4 ms 3456 KB Output is correct
9 Correct 4 ms 3456 KB Output is correct
10 Correct 3 ms 3456 KB Output is correct
11 Correct 3 ms 3456 KB Output is correct
12 Correct 4 ms 3456 KB Output is correct
13 Correct 3 ms 3456 KB Output is correct
14 Correct 4 ms 3456 KB Output is correct
15 Correct 209 ms 68856 KB Output is correct
16 Correct 221 ms 68600 KB Output is correct
17 Correct 252 ms 68984 KB Output is correct
18 Correct 280 ms 69880 KB Output is correct
19 Correct 250 ms 70136 KB Output is correct
20 Correct 432 ms 71160 KB Output is correct
21 Correct 216 ms 68296 KB Output is correct
22 Correct 235 ms 67960 KB Output is correct
23 Correct 228 ms 68216 KB Output is correct
24 Correct 363 ms 69368 KB Output is correct
25 Correct 314 ms 71320 KB Output is correct
26 Correct 281 ms 68344 KB Output is correct
27 Correct 248 ms 68092 KB Output is correct
28 Correct 261 ms 68348 KB Output is correct
29 Correct 319 ms 69240 KB Output is correct
30 Correct 310 ms 70264 KB Output is correct
31 Correct 231 ms 68472 KB Output is correct
32 Correct 224 ms 68216 KB Output is correct
33 Correct 244 ms 68472 KB Output is correct
34 Correct 299 ms 69624 KB Output is correct
35 Correct 376 ms 71416 KB Output is correct
36 Correct 262 ms 69496 KB Output is correct