oj.uz

Submission #260345

# Submission time Handle Problem Language Result Execution time Memory
260345 2020-08-10T06:17:40 Z arnold518 Valley (BOI19_valley) C++14
100 / 100
 359 ms 53496 KB 
#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;

const int MAXN = 1e5;
const ll INF = 1e18;

struct Edge
{
	int u, v, w;
};

int N, S, Q, E;
Edge A[MAXN+10];
vector<pii> adj[MAXN+10];
bool P[MAXN+10];

int L[MAXN+10], R[MAXN+10], dep[MAXN+10], cnt, par[MAXN+10][30];
ll dist[MAXN+10], dp[MAXN+10][30];

void dfs(int now, int bef, int depp, ll distt)
{
	dep[now]=depp;
	dist[now]=distt;
	L[now]=++cnt;
	par[now][0]=bef;
	dp[now][0]=INF;
	if(P[now]) dp[now][0]=distt;
	for(auto &nxt : adj[now])
	{
		if(nxt.first==bef) continue;
		dfs(nxt.first, now, depp+1, distt+nxt.second);
		dp[now][0]=min(dp[now][0], dp[nxt.first][0]);
	}
	R[now]=cnt;
}

int main()
{
	scanf("%d%d%d%d", &N, &S, &Q, &E);
	for(int i=1; i<N; i++)
	{
		int u, v, w;
		scanf("%d%d%d", &u, &v, &w);
		adj[u].push_back({v, w});
		adj[v].push_back({u, w});
		A[i]={u, v, w};
	}
	for(int i=1; i<=S; i++)
	{
		int t;
		scanf("%d", &t);
		P[t]=1;
	}
	dfs(E, E, 1, 0);
	for(int i=1; i<=N; i++) dp[i][0]-=2*dist[i];
	for(int i=1; i<N; i++) if(dep[A[i].u]>dep[A[i].v]) swap(A[i].u, A[i].v);

	for(int i=1; i<=20; i++) for(int j=1; j<=N; j++)
	{
		par[j][i]=par[par[j][i-1]][i-1];
		dp[j][i]=min(dp[j][i-1], dp[par[j][i-1]][i-1]);
	}

	while(Q--)
	{
		int t, u;
		scanf("%d%d", &t, &u);
		int v=A[t].v;
		if(!(L[v]<=L[u] && R[u]<=R[v])) printf("escaped\n");
		else
		{
			ll val=1e17;
			int now=u;
			for(int i=20; i>=0; i--)
			{
				if(dep[par[now][i]]>=dep[v])
				{
					val=min(val, dp[now][i]);
					now=par[now][i];
				}
			}
			val=min(val, dp[v][0]);
			if(val==(ll)1e17) printf("oo\n");
			else printf("%lld\n", val+dist[u]);
		}
	}
}

Compilation message

valley.cpp: In function 'int main()':
valley.cpp:43:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d%d%d", &N, &S, &Q, &E);
  ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~
valley.cpp:47:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d%d%d", &u, &v, &w);
   ~~~~~^~~~~~~~~~~~~~~~~~~~~~
valley.cpp:55:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d", &t);
   ~~~~~^~~~~~~~~~
valley.cpp:71:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d%d", &t, &u);
   ~~~~~^~~~~~~~~~~~~~~~

Subtask #1
9.0 / 9.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 2816 KB Output is correct
2 Correct 7 ms 2944 KB Output is correct
3 Correct 6 ms 2944 KB Output is correct
4 Correct 6 ms 2816 KB Output is correct

Subtask #2
27.0 / 27.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 2816 KB Output is correct
2 Correct 7 ms 2944 KB Output is correct
3 Correct 6 ms 2944 KB Output is correct
4 Correct 6 ms 2816 KB Output is correct
5 Correct 3 ms 3200 KB Output is correct
6 Correct 3 ms 3200 KB Output is correct
7 Correct 3 ms 3200 KB Output is correct
8 Correct 3 ms 3200 KB Output is correct
9 Correct 3 ms 3200 KB Output is correct
10 Correct 4 ms 3200 KB Output is correct
11 Correct 3 ms 3200 KB Output is correct
12 Correct 4 ms 3200 KB Output is correct
13 Correct 3 ms 3200 KB Output is correct
14 Correct 3 ms 3200 KB Output is correct

Subtask #3
23.0 / 23.0

# Verdict Execution time Memory Grader output
1 Correct 224 ms 45704 KB Output is correct
2 Correct 249 ms 45368 KB Output is correct
3 Correct 250 ms 45304 KB Output is correct
4 Correct 268 ms 47096 KB Output is correct
5 Correct 242 ms 47356 KB Output is correct
6 Correct 278 ms 49016 KB Output is correct

Subtask #4
41.0 / 41.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 2816 KB Output is correct
2 Correct 7 ms 2944 KB Output is correct
3 Correct 6 ms 2944 KB Output is correct
4 Correct 6 ms 2816 KB Output is correct
5 Correct 3 ms 3200 KB Output is correct
6 Correct 3 ms 3200 KB Output is correct
7 Correct 3 ms 3200 KB Output is correct
8 Correct 3 ms 3200 KB Output is correct
9 Correct 3 ms 3200 KB Output is correct
10 Correct 4 ms 3200 KB Output is correct
11 Correct 3 ms 3200 KB Output is correct
12 Correct 4 ms 3200 KB Output is correct
13 Correct 3 ms 3200 KB Output is correct
14 Correct 3 ms 3200 KB Output is correct
15 Correct 224 ms 45704 KB Output is correct
16 Correct 249 ms 45368 KB Output is correct
17 Correct 250 ms 45304 KB Output is correct
18 Correct 268 ms 47096 KB Output is correct
19 Correct 242 ms 47356 KB Output is correct
20 Correct 278 ms 49016 KB Output is correct
21 Correct 204 ms 49016 KB Output is correct
22 Correct 220 ms 48632 KB Output is correct
23 Correct 225 ms 48760 KB Output is correct
24 Correct 252 ms 50552 KB Output is correct
25 Correct 259 ms 53496 KB Output is correct
26 Correct 208 ms 49016 KB Output is correct
27 Correct 216 ms 48632 KB Output is correct
28 Correct 231 ms 48712 KB Output is correct
29 Correct 283 ms 50040 KB Output is correct
30 Correct 359 ms 51448 KB Output is correct
31 Correct 269 ms 49272 KB Output is correct
32 Correct 242 ms 48760 KB Output is correct
33 Correct 253 ms 48760 KB Output is correct
34 Correct 284 ms 50564 KB Output is correct
35 Correct 274 ms 53496 KB Output is correct
36 Correct 236 ms 50808 KB Output is correct