oj.uz

답안 #125559

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
125559 2019-07-05T23:49:53 Z eriksuenderhauf Valley (BOI19_valley) C++11
100 / 100
 289 ms 39772 KB 
#include <bits/stdc++.h>
#define pii pair<int,int>
#define pil pair<int,long long>
#define vii vector<pii>
#define vil vector<pil>
#define pb push_back
#define fi first
#define se second
#define mp make_pair
using namespace std;
typedef long long ll;
const int MAXN = 1e5 + 5;
const ll INF = 1e18 + 7;
int par[19][MAXN], dep[MAXN];
int sh[MAXN], mrk[MAXN];
ll depth[MAXN], nx2[MAXN], nxPar[19][MAXN];
vil adj[MAXN];
pair<pii,ll> edg[MAXN];

void dfs(int u, int p, ll d, int d2) {
	depth[u] = d;
	dep[u] = d2;
	if (mrk[u]) 
		nx2[u] = d;
	else 
		nx2[u] = INF;
	for (pil nx: adj[u]) {
		int v; ll w;
		tie(v, w) = nx;
		if (v == p) continue;
		par[0][v] = u;
		dfs(v, u, d+w, d2+1);
		nx2[u] = min(nx2[u], nx2[v]);
	}
}

int lca(int u, int v) {
	if (dep[u] > dep[v]) swap(u, v);
	int d = dep[v]-dep[u];
	for (int i = 0; i < 19; i++)
		if ((d >> i) & 1)
			v = par[i][v];
	if (u == v) return u;
	for (int i = 18; i > -1; i--)
		if (par[i][u] != par[i][v])
			v = par[i][v], u = par[i][u];
	return par[0][u];
}

int main() {
	int n, s, q, e;
	scanf("%d %d %d %d", &n, &s, &q, &e);
	e--;
	for (int i = 1; i < n; i++) {
		int u, v, w;
		scanf("%d %d %d", &u, &v, &w);
		u--, v--;
		adj[u].pb(mp(v, w));
		adj[v].pb(mp(u, w));
		edg[i-1]=mp(mp(u,v),w);
	}
	for (int j = 0; j < s; j++) {
		scanf("%d", &sh[j]);
		mrk[--sh[j]] = 1;
	}
	dfs(e, -1, 0, 0);
	for (int i = 0; i < n; i++)
		if (nx2[i] != INF)
			nx2[i] -= 2*depth[i];
	for (int i = 0; i < n; i++)
		nxPar[0][i] = min(nx2[par[0][i]], nx2[i]);
	for (int i = 1; i < 19; i++) {
		for (int j = 0; j < n; j++) {
			par[i][j] = par[i-1][par[i-1][j]];
			nxPar[i][j] = min(nxPar[i-1][j],nxPar[i-1][par[i-1][j]]);
		}
	}
	while (q--) {
		int i, r;
		scanf("%d %d", &i, &r);
		i--, r--;
		int u, v;
		tie(u,v)=edg[i].fi;
		if (dep[u] < dep[v])
			swap(u,v);
		if (lca(r,u) != u) {
			printf("escaped\n");
			continue;
		}
		if (mrk[r]) {
			printf("0\n");
			continue;
		}
		int r0 = r;
		ll ans = nx2[r];
		int delta = dep[r] - dep[u];
		for (int i = 18; i > -1; i--)
			if ((delta >> i) & 1) {
				ans = min(ans, nxPar[i][r]);
				r = par[i][r];
			}
		if (ans == INF)
			printf("oo\n");
		else
			printf("%lld\n", ans+depth[r0]);
	}
	return 0;
}

Compilation message

valley.cpp: In function 'int main()':
valley.cpp:52:7: 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:56:8: 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:63:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d", &sh[j]);
   ~~~~~^~~~~~~~~~~~~~
valley.cpp:80:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d %d", &i, &r);
   ~~~~~^~~~~~~~~~~~~~~~~

Subtask #1
9.0 / 9.0

# 결과 실행 시간 메모리 Grader output
1 Correct 8 ms 2936 KB Output is correct
2 Correct 8 ms 2936 KB Output is correct
3 Correct 8 ms 2936 KB Output is correct
4 Correct 8 ms 2936 KB Output is correct

Subtask #2
27.0 / 27.0

# 결과 실행 시간 메모리 Grader output
1 Correct 8 ms 2936 KB Output is correct
2 Correct 8 ms 2936 KB Output is correct
3 Correct 8 ms 2936 KB Output is correct
4 Correct 8 ms 2936 KB Output is correct
5 Correct 5 ms 3192 KB Output is correct
6 Correct 5 ms 3192 KB Output is correct
7 Correct 5 ms 3192 KB Output is correct
8 Correct 5 ms 3192 KB Output is correct
9 Correct 5 ms 3192 KB Output is correct
10 Correct 5 ms 3192 KB Output is correct
11 Correct 5 ms 3192 KB Output is correct
12 Correct 5 ms 3192 KB Output is correct
13 Correct 6 ms 3320 KB Output is correct
14 Correct 7 ms 3192 KB Output is correct

Subtask #3
23.0 / 23.0

# 결과 실행 시간 메모리 Grader output
1 Correct 229 ms 35164 KB Output is correct
2 Correct 213 ms 34936 KB Output is correct
3 Correct 229 ms 35196 KB Output is correct
4 Correct 228 ms 36984 KB Output is correct
5 Correct 243 ms 37244 KB Output is correct
6 Correct 244 ms 39356 KB Output is correct

Subtask #4
41.0 / 41.0

# 결과 실행 시간 메모리 Grader output
1 Correct 8 ms 2936 KB Output is correct
2 Correct 8 ms 2936 KB Output is correct
3 Correct 8 ms 2936 KB Output is correct
4 Correct 8 ms 2936 KB Output is correct
5 Correct 5 ms 3192 KB Output is correct
6 Correct 5 ms 3192 KB Output is correct
7 Correct 5 ms 3192 KB Output is correct
8 Correct 5 ms 3192 KB Output is correct
9 Correct 5 ms 3192 KB Output is correct
10 Correct 5 ms 3192 KB Output is correct
11 Correct 5 ms 3192 KB Output is correct
12 Correct 5 ms 3192 KB Output is correct
13 Correct 6 ms 3320 KB Output is correct
14 Correct 7 ms 3192 KB Output is correct
15 Correct 229 ms 35164 KB Output is correct
16 Correct 213 ms 34936 KB Output is correct
17 Correct 229 ms 35196 KB Output is correct
18 Correct 228 ms 36984 KB Output is correct
19 Correct 243 ms 37244 KB Output is correct
20 Correct 244 ms 39356 KB Output is correct
21 Correct 175 ms 34424 KB Output is correct
22 Correct 235 ms 34260 KB Output is correct
23 Correct 202 ms 34424 KB Output is correct
24 Correct 224 ms 36512 KB Output is correct
25 Correct 256 ms 39544 KB Output is correct
26 Correct 179 ms 34680 KB Output is correct
27 Correct 191 ms 34512 KB Output is correct
28 Correct 218 ms 34680 KB Output is correct
29 Correct 253 ms 36216 KB Output is correct
30 Correct 289 ms 37756 KB Output is correct
31 Correct 187 ms 34812 KB Output is correct
32 Correct 205 ms 34756 KB Output is correct
33 Correct 215 ms 34992 KB Output is correct
34 Correct 236 ms 36856 KB Output is correct
35 Correct 262 ms 39772 KB Output is correct
36 Correct 214 ms 37368 KB Output is correct