oj.uz

Submission #951682

# Submission time Handle Problem Language Result Execution time Memory
951682 2024-03-22T10:18:57 Z kilkuwu Stations (IOI20_stations) C++17
100 / 100
 600 ms 1484 KB 
#ifndef LOCAL
#include "stations.h"
#else
#include <vector>

std::vector<int> label(int n, int k, std::vector<int> u, std::vector<int> v);
int find_next_station(int s, int t, std::vector<int> c);

#include <cstdio>
#include <cassert>
#include <map>
#include <vector>
#include <algorithm>

static int __max_label = 0;
static int __r, __n, __k, __q;
static std::vector<int> __u, __v, __labels, __answers;
static std::map<int, int> __reverse_labels;
static std::vector<std::vector<int>> __adjlist;
static int __s, __t, __w;
static std::vector<int> __c;

int main() {
	assert(scanf("%d", &__r) == 1);
	for (int tc = 0; tc < __r; tc++) {
		assert(scanf("%d%d", &__n, &__k) == 2);
		__u.resize(__n - 1);
		__v.resize(__n - 1);
		__adjlist.clear();
		__adjlist.resize(__n);
		for (int i = 0; i < __n - 1; i++) {
			assert(scanf("%d%d", &__u[i], &__v[i]) == 2);
			__adjlist[__u[i]].push_back(__v[i]);
			__adjlist[__v[i]].push_back(__u[i]);
		}
		__labels = label(__n, __k, __u, __v);
		if ((int)__labels.size() != __n) {
			printf("Number of labels not equal to %d\n", __n);
			exit(0);
		}
		__reverse_labels.clear();
		for (int i = 0; i < __n; i++) {
			if (__labels[i] < 0 || __labels[i] > __k) {
				printf("Label not in range 0 to %d\n", __k);
				exit(0);
			}
			if (__reverse_labels.find(__labels[i]) != __reverse_labels.end()) {
				printf("Labels not unique\n");
				exit(0);
			}
			__reverse_labels[__labels[i]] = i;
			if (__labels[i] > __max_label) {
				__max_label = __labels[i];
			}
		}
		assert(scanf("%d", &__q) == 1);
		for (int i = 0; i < __q; i++) {
			assert(scanf("%d%d%d", &__s, &__t, &__w) == 3);
			__c.clear();
			for (int v : __adjlist[__s]) {
				__c.push_back(__labels[v]);
			}
			std::sort(__c.begin(), __c.end());
			int answer = find_next_station(__labels[__s], __labels[__t], __c);
			if (!std::binary_search(__c.begin(), __c.end(), answer)) {
				printf("Label %d returned by find_next_station not found in c\n", answer);
				exit(0);
			}
			__answers.push_back(__reverse_labels[answer]);
		}
	}
	printf("%d\n", __max_label);
	for (int index : __answers) {
		printf("%d\n", index);
	}
	exit(0);
}
#endif
#include <bits/stdc++.h>

std::vector<int> label(int n, int k, std::vector<int> u, std::vector<int> v) {
  std::vector<std::vector<int>> adj(n);
  std::vector<int> st(n), en(n), dep(n);
  for (int i = 0; i + 1 < n; i++) {
    adj[u[i]].push_back(v[i]); 
    adj[v[i]].push_back(u[i]);
  }

  int ti = 0;
  std::function<void(int, int)> dfs = [&](int x, int p) -> void {
    st[x] = ti++;
    for (int y : adj[x]) {
      if (y == p) continue;
      dep[y] = dep[x] + 1;
      dfs(y, x);
    }
    en[x] = ti++;
  };

  dfs(0, 0);

  std::vector<int> res(n);
  for (int i = 0; i < n; i++) {
    if (dep[i] & 1) {
      res[i] = en[i];
    } else {
      res[i] = st[i];
    }
  }

  std::vector<int> vals = res;
  std::sort(vals.begin(), vals.end());
  for (int i = 0; i < n; i++) {
    res[i] = std::lower_bound(vals.begin(), vals.end(), res[i]) - vals.begin();
  }

  return res;
}

int find_next_station(int s, int t, std::vector<int> c) {
  int sz = c.size();
  if (s == 0) {
    // we know this guy the root 
    int st = 1;
    for (int i = 0; i < sz; i++) {
      if (st <= t && t <= c[i]) {
        return c[i];
      }
      st = c[i] + 1;
    }
    return c.back();
  }
  
  if (s < c[0]) {
    // this means this guy is st 

    // biggest is the out

    int st = s + 1;
    for (int i = 0; i + 1 < sz; i++) {
      if (st <= t && t <= c[i]) {
        return c[i];
      }
      st = c[i] + 1;
    }
    
    return c.back();
  } else {
    int en = s - 1;
    for (int i = sz - 1; i > 0; i--) {
      if (c[i] <= t && t <= en) {
        return c[i];
      }
      en = c[i] - 1;
    }
    return c[0];
  }
}

Subtask #1
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 309 ms 944 KB Output is correct
2 Correct 275 ms 1120 KB Output is correct
3 Correct 561 ms 1192 KB Output is correct
4 Correct 358 ms 688 KB Output is correct
5 Correct 399 ms 684 KB Output is correct
6 Correct 306 ms 1188 KB Output is correct
7 Correct 284 ms 684 KB Output is correct
8 Correct 1 ms 768 KB Output is correct
9 Correct 3 ms 772 KB Output is correct
10 Correct 1 ms 768 KB Output is correct

Subtask #2
8.0 / 8.0

# Verdict Execution time Memory Grader output
1 Correct 314 ms 868 KB Output is correct
2 Correct 349 ms 792 KB Output is correct
3 Correct 546 ms 684 KB Output is correct
4 Correct 424 ms 684 KB Output is correct
5 Correct 374 ms 684 KB Output is correct
6 Correct 276 ms 684 KB Output is correct

Subtask #3
16.0 / 16.0

# Verdict Execution time Memory Grader output
1 Correct 337 ms 956 KB Output is correct
2 Correct 277 ms 956 KB Output is correct
3 Correct 570 ms 684 KB Output is correct
4 Correct 423 ms 684 KB Output is correct
5 Correct 366 ms 684 KB Output is correct
6 Correct 285 ms 924 KB Output is correct
7 Correct 268 ms 696 KB Output is correct
8 Correct 2 ms 768 KB Output is correct
9 Correct 3 ms 972 KB Output is correct
10 Correct 1 ms 772 KB Output is correct
11 Correct 355 ms 684 KB Output is correct
12 Correct 280 ms 1452 KB Output is correct
13 Correct 305 ms 1036 KB Output is correct
14 Correct 302 ms 940 KB Output is correct
15 Correct 36 ms 872 KB Output is correct
16 Correct 38 ms 880 KB Output is correct
17 Correct 65 ms 1124 KB Output is correct

Subtask #4
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 571 ms 684 KB Output is correct
2 Correct 427 ms 684 KB Output is correct
3 Correct 393 ms 688 KB Output is correct
4 Correct 2 ms 764 KB Output is correct
5 Correct 3 ms 768 KB Output is correct
6 Correct 1 ms 764 KB Output is correct
7 Correct 363 ms 940 KB Output is correct
8 Correct 545 ms 936 KB Output is correct
9 Correct 434 ms 684 KB Output is correct
10 Correct 344 ms 684 KB Output is correct
11 Correct 4 ms 768 KB Output is correct
12 Correct 2 ms 768 KB Output is correct
13 Correct 2 ms 1024 KB Output is correct
14 Correct 3 ms 768 KB Output is correct
15 Correct 1 ms 772 KB Output is correct
16 Correct 317 ms 684 KB Output is correct
17 Correct 308 ms 684 KB Output is correct
18 Correct 318 ms 684 KB Output is correct
19 Correct 340 ms 684 KB Output is correct
20 Correct 325 ms 684 KB Output is correct

Subtask #5
61.0 / 61.0

# Verdict Execution time Memory Grader output
1 Correct 360 ms 944 KB Output is correct
2 Correct 263 ms 1196 KB Output is correct
3 Correct 555 ms 684 KB Output is correct
4 Correct 413 ms 684 KB Output is correct
5 Correct 356 ms 684 KB Output is correct
6 Correct 295 ms 1128 KB Output is correct
7 Correct 326 ms 684 KB Output is correct
8 Correct 2 ms 760 KB Output is correct
9 Correct 3 ms 768 KB Output is correct
10 Correct 0 ms 764 KB Output is correct
11 Correct 284 ms 872 KB Output is correct
12 Correct 370 ms 992 KB Output is correct
13 Correct 600 ms 684 KB Output is correct
14 Correct 418 ms 684 KB Output is correct
15 Correct 343 ms 684 KB Output is correct
16 Correct 289 ms 684 KB Output is correct
17 Correct 387 ms 688 KB Output is correct
18 Correct 302 ms 1184 KB Output is correct
19 Correct 295 ms 1328 KB Output is correct
20 Correct 288 ms 684 KB Output is correct
21 Correct 35 ms 792 KB Output is correct
22 Correct 46 ms 820 KB Output is correct
23 Correct 59 ms 944 KB Output is correct
24 Correct 3 ms 768 KB Output is correct
25 Correct 2 ms 768 KB Output is correct
26 Correct 3 ms 768 KB Output is correct
27 Correct 3 ms 764 KB Output is correct
28 Correct 0 ms 968 KB Output is correct
29 Correct 357 ms 684 KB Output is correct
30 Correct 340 ms 684 KB Output is correct
31 Correct 331 ms 684 KB Output is correct
32 Correct 318 ms 684 KB Output is correct
33 Correct 322 ms 684 KB Output is correct
34 Correct 202 ms 1168 KB Output is correct
35 Correct 305 ms 1220 KB Output is correct
36 Correct 303 ms 1192 KB Output is correct
37 Correct 301 ms 1392 KB Output is correct
38 Correct 285 ms 1136 KB Output is correct
39 Correct 274 ms 1236 KB Output is correct
40 Correct 310 ms 1160 KB Output is correct
41 Correct 298 ms 1156 KB Output is correct
42 Correct 31 ms 904 KB Output is correct
43 Correct 60 ms 872 KB Output is correct
44 Correct 87 ms 864 KB Output is correct
45 Correct 132 ms 868 KB Output is correct
46 Correct 193 ms 864 KB Output is correct
47 Correct 207 ms 912 KB Output is correct
48 Correct 38 ms 960 KB Output is correct
49 Correct 35 ms 1484 KB Output is correct