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Submission #310389

# Submission time Handle Problem Language Result Execution time Memory
310389 2020-10-06T20:17:03 Z rqi Valley (BOI19_valley) C++14
100 / 100
 509 ms 28408 KB 
#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef vector<int> vi;

#define f first
#define s second
#define pb push_back
#define mp make_pair

const int mx = 100005;
const ll INF = 1e18;
const ll BIG = 1e15;
int N, S, Q, E;
vector<pair<int, ll>> adj[mx];
int A[mx];
int B[mx];
ll W[mx];
bool isShop[mx];
int I[mx];
int R[mx];

bool esc[mx];
ll ans[mx];

vi queries[mx]; //queries at this node
bool inPath[mx];

void findPath(int node, int prv = -1){
	inPath[node] = 1;
	for(auto u: queries[node]){
		if(!inPath[A[I[u]]] || !inPath[B[I[u]]]){
			esc[u] = 1;
		}
	}

	for(auto u: adj[node]){
		if(u.f == prv) continue;
		findPath(u.f, node);
	}
	inPath[node] = 0;
}

ll dist[mx];
int depth[mx];
ll shop[mx]; //lowest shop dist

void genDists(int node, ll cdist = 0, int cdepth = 0, int prv = -1){
	dist[node] = cdist;
	depth[node] = cdepth;
	shop[node] = INF;

	if(isShop[node]){
		shop[node] = min(shop[node], dist[node]);
	}

	for(auto u: adj[node]){
		if(u.f == prv) continue;
		genDists(u.f, cdist+u.s, cdepth+1, node);
		shop[node] = min(shop[node], shop[u.f]);
	}
}

pair<int, ll> par[mx];
pair<int, ll> jmp[mx];

void genPar(int node, int prv = -1){
	if(node == E){
		par[node] = mp(node, INF);
		jmp[node] = mp(node, INF);
	}
	else{
		int p = par[node].f;
		if(depth[p]-depth[jmp[p].f] == depth[jmp[p].f]-depth[jmp[jmp[p].f].f]){
			jmp[node] = mp(jmp[jmp[p].f].f, min(par[node].s, min(jmp[p].s, jmp[jmp[p].f].s)));
		}
		else{
			jmp[node] = par[node];
		}
	}

	for(auto u: adj[node]){
		if(u.f == prv) continue;
		par[u.f] = mp(node, shop[node]);
		genPar(u.f, node);
	}
}

int main(){	
	cin >> N >> S >> Q >> E;
	for(int i = 1; i < N; i++){
		cin >> A[i] >> B[i] >> W[i];
		adj[A[i]].pb(mp(B[i], W[i]));
		adj[B[i]].pb(mp(A[i], W[i]));
	}

	for(int i = 1; i <= S; i++){
		int C;
		cin >> C;
		isShop[C] = 1;
	}

	for(int i = 1; i <= Q; i++){
		cin >> I[i] >> R[i];
		queries[R[i]].pb(i);
	}
	
	findPath(E); //modify esc
	genDists(E); //gen dist and depth
	for(int i = 1; i <= N; i++){
		shop[i]-=2*dist[i];
	}

	genPar(E);

	for(int i = 1; i <= Q; i++){
		if(esc[i]) continue;
		int topnode = max(mp(depth[A[I[i]]], A[I[i]]), mp(depth[B[I[i]]], B[I[i]])).s;
		int curnode = R[i];
		ll curans = shop[R[i]];
		while(curnode != topnode){
			if(depth[jmp[curnode].f] >= depth[topnode]){
				curans = min(curans, jmp[curnode].s);
				curnode = jmp[curnode].f;
			}
			else{
				curans = min(curans, par[curnode].s);
				curnode = par[curnode].f;
			}
		}
		ans[i] = curans+dist[R[i]];
	}
	for(int i = 1; i <= Q; i++){
		if(esc[i]){
			cout << "escaped" << "\n"; 
		}
		else{
			if(ans[i] >= BIG){
				cout << "oo" << "\n";
			}
			else{
				cout << ans[i] << "\n";
			}
		}
	}

}

Subtask #1
9.0 / 9.0

# Verdict Execution time Memory Grader output
1 Correct 12 ms 5504 KB Output is correct
2 Correct 12 ms 5504 KB Output is correct
3 Correct 12 ms 5504 KB Output is correct
4 Correct 12 ms 5504 KB Output is correct

Subtask #2
27.0 / 27.0

# Verdict Execution time Memory Grader output
1 Correct 12 ms 5504 KB Output is correct
2 Correct 12 ms 5504 KB Output is correct
3 Correct 12 ms 5504 KB Output is correct
4 Correct 12 ms 5504 KB Output is correct
5 Correct 7 ms 5248 KB Output is correct
6 Correct 7 ms 5248 KB Output is correct
7 Correct 7 ms 5248 KB Output is correct
8 Correct 7 ms 5248 KB Output is correct
9 Correct 7 ms 5248 KB Output is correct
10 Correct 7 ms 5248 KB Output is correct
11 Correct 7 ms 5248 KB Output is correct
12 Correct 7 ms 5376 KB Output is correct
13 Correct 7 ms 5248 KB Output is correct
14 Correct 6 ms 5248 KB Output is correct

Subtask #3
23.0 / 23.0

# Verdict Execution time Memory Grader output
1 Correct 475 ms 25252 KB Output is correct
2 Correct 509 ms 24952 KB Output is correct
3 Correct 489 ms 25080 KB Output is correct
4 Correct 499 ms 26744 KB Output is correct
5 Correct 469 ms 25848 KB Output is correct
6 Correct 505 ms 28152 KB Output is correct

Subtask #4
41.0 / 41.0

# Verdict Execution time Memory Grader output
1 Correct 12 ms 5504 KB Output is correct
2 Correct 12 ms 5504 KB Output is correct
3 Correct 12 ms 5504 KB Output is correct
4 Correct 12 ms 5504 KB Output is correct
5 Correct 7 ms 5248 KB Output is correct
6 Correct 7 ms 5248 KB Output is correct
7 Correct 7 ms 5248 KB Output is correct
8 Correct 7 ms 5248 KB Output is correct
9 Correct 7 ms 5248 KB Output is correct
10 Correct 7 ms 5248 KB Output is correct
11 Correct 7 ms 5248 KB Output is correct
12 Correct 7 ms 5376 KB Output is correct
13 Correct 7 ms 5248 KB Output is correct
14 Correct 6 ms 5248 KB Output is correct
15 Correct 475 ms 25252 KB Output is correct
16 Correct 509 ms 24952 KB Output is correct
17 Correct 489 ms 25080 KB Output is correct
18 Correct 499 ms 26744 KB Output is correct
19 Correct 469 ms 25848 KB Output is correct
20 Correct 505 ms 28152 KB Output is correct
21 Correct 414 ms 24632 KB Output is correct
22 Correct 427 ms 24440 KB Output is correct
23 Correct 433 ms 24312 KB Output is correct
24 Correct 449 ms 26488 KB Output is correct
25 Correct 442 ms 28408 KB Output is correct
26 Correct 410 ms 24696 KB Output is correct
27 Correct 424 ms 24472 KB Output is correct
28 Correct 437 ms 24468 KB Output is correct
29 Correct 450 ms 25848 KB Output is correct
30 Correct 449 ms 26488 KB Output is correct
31 Correct 408 ms 24824 KB Output is correct
32 Correct 428 ms 24568 KB Output is correct
33 Correct 448 ms 24824 KB Output is correct
34 Correct 455 ms 26360 KB Output is correct
35 Correct 440 ms 28408 KB Output is correct
36 Correct 408 ms 26104 KB Output is correct