oj.uz

Submission #1079539

# Submission time Handle Problem Language Result Execution time Memory
1079539 2024-08-28T16:30:55 Z anango Stations (IOI20_stations) C++17
73.357 / 100
 675 ms 1304 KB 
#include "stations.h"
#include <vector>
#include <bits/stdc++.h>
using namespace std;
#define cout cerr


vector<vector<int>> adjlist;

vector<int> depth;
vector<int> tin;
vector<int> tout;
int tim = 0;

void dfs(int node, int par) {
    tin[node] = tim++;
    for (int j:adjlist[node]) {
        if (j!=par) {
            depth[j] = depth[node]+1;
            dfs(j,node);
        }
    }
    tout[node] = tim++;
}

std::vector<int> label(int n, int k, std::vector<int> u, std::vector<int> v) {
    tim = 0;
	std::vector<int> labels(n);
    adjlist=vector<vector<int>>(n);
    tin=tout=vector<int>(n,-1);
    depth=vector<int>(n,0);
    for (int i=0; i<n-1; i++) {
        adjlist[u[i]].push_back(v[i]);
        adjlist[v[i]].push_back(u[i]);
    }
    dfs(0,-1);
	for (int i = 0; i < n; i++) {
        if (depth[i]%2==1) {
		    labels[i] = tin[i];
        }
        else {
            labels[i] = 2003+tout[i];
        }
        //cout << i << " " << tin[i] <<" " << tout[i] <<" " << labels[i] << endl;
	}

    //consider using the euler tour trick on the tree
    //for each node, store the left and right times of its subtree in the label (using perfect hashing)
    //for a node, you know the tin and tout (call these inv and outv)
    //then for every child, you also know the tin and tout of that child (call these inc and outc)
    //and the tin and tout of the destination (call these ind and outd)
    //so you know that if inv<=ind<=outd<=outv, then the destination is in this subtree
    //and if inc<=ind<=outd<=outc for some child, the destination is in the subtree of this child
    //if none of these hold, then go up
    //this uses at most n^2 labels
    //we could just use in but then it jambloats because we don't know where the subtree ends
    //actually what about storing out for even depth
    //because we know one of the in values for child for free
    //and if we know out[node] we know one out value for free
    //that should work for 2000

	return labels;
}

int find_next_station(int s, int t, std::vector<int> c) {
    sort(c.begin(), c.end());

    //cout << "TRY FIND " << endl;
    for (auto i:c) {
        //cout << i <<" ";
    }
    //cout << endl;
    //cout << "DOING " << s <<" " << t << endl;
    if (t>=2003) {
        t-=2003;
    }
    if (s>=2003) {
        //depth is even
        s-=2003;
        //so all the children are in-values, our node is an out-value
        //the lowest in-value is actually the parent, so that can be ignored
        c.push_back(s+1);
        sort(c.begin(), c.end());
        //cout << s <<" " << c.size() << endl;
        for (auto i:c) {
            //cout << i <<" ";
            assert(i<2003);
        }
        //cout << endl;
        for (int i=2; i<c.size(); i++) {
            if (c[i-1]<=t && t<c[i]) {
                return c[i-1];
            }
        }
        return c[0];
    }
    else {
        //depth is odd
        for (int i=0; i<c.size(); i++) {
            c[i]-=2003;
        }
        //so all the children are out-values, our node is an in-value
        //max value is actually the parent
        c.push_back(s+1);
        sort(c.begin(), c.end());
        //assert(c.front()==s+1);   
        ////cout << "DOCTORED C " << endl;
        for (auto i:c) {
            //cout << i <<" ";
        }
        //cout << endl;
        for (int i=1; i<((int)c.size())-1; i++) {
            if (c[i-1]<=t && t<=c[i]) {
                return c[i]+2003;
            }
        }
        return c.back()+2003;
    }
	return c[0];
}

Compilation message

stations.cpp: In function 'int find_next_station(int, int, std::vector<int>)':
stations.cpp:69:15: warning: unused variable 'i' [-Wunused-variable]
   69 |     for (auto i:c) {
      |               ^
stations.cpp:90:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   90 |         for (int i=2; i<c.size(); i++) {
      |                       ~^~~~~~~~~
stations.cpp:99:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   99 |         for (int i=0; i<c.size(); i++) {
      |                       ~^~~~~~~~~
stations.cpp:108:19: warning: unused variable 'i' [-Wunused-variable]
  108 |         for (auto i:c) {
      |                   ^

Subtask #1
0 / 5.0

# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 600 KB Invalid labels (values out of range). scenario=0, k=1000, vertex=0, label=2022
2 Halted 0 ms 0 KB -

Subtask #2
0 / 8.0

# Verdict Execution time Memory Grader output
1 Incorrect 3 ms 344 KB Invalid labels (values out of range). scenario=0, k=1000, vertex=0, label=3994
2 Halted 0 ms 0 KB -

Subtask #3
16.0 / 16.0

# Verdict Execution time Memory Grader output
1 Correct 357 ms 776 KB Output is correct
2 Correct 343 ms 944 KB Output is correct
3 Correct 675 ms 684 KB Output is correct
4 Correct 482 ms 940 KB Output is correct
5 Correct 403 ms 684 KB Output is correct
6 Correct 296 ms 940 KB Output is correct
7 Correct 303 ms 684 KB Output is correct
8 Correct 1 ms 760 KB Output is correct
9 Correct 2 ms 768 KB Output is correct
10 Correct 0 ms 768 KB Output is correct
11 Correct 410 ms 684 KB Output is correct
12 Correct 336 ms 1068 KB Output is correct
13 Correct 365 ms 1188 KB Output is correct
14 Correct 327 ms 684 KB Output is correct
15 Correct 37 ms 768 KB Output is correct
16 Correct 43 ms 768 KB Output is correct
17 Correct 62 ms 716 KB Output is correct

Subtask #4
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 635 ms 684 KB Output is correct
2 Correct 453 ms 684 KB Output is correct
3 Correct 416 ms 684 KB Output is correct
4 Correct 1 ms 768 KB Output is correct
5 Correct 2 ms 768 KB Output is correct
6 Correct 1 ms 768 KB Output is correct
7 Correct 399 ms 684 KB Output is correct
8 Correct 635 ms 684 KB Output is correct
9 Correct 483 ms 712 KB Output is correct
10 Correct 482 ms 684 KB Output is correct
11 Correct 2 ms 768 KB Output is correct
12 Correct 2 ms 776 KB Output is correct
13 Correct 2 ms 764 KB Output is correct
14 Correct 1 ms 768 KB Output is correct
15 Correct 2 ms 776 KB Output is correct
16 Correct 358 ms 684 KB Output is correct
17 Correct 381 ms 684 KB Output is correct
18 Correct 359 ms 684 KB Output is correct
19 Correct 346 ms 684 KB Output is correct
20 Correct 386 ms 684 KB Output is correct

Subtask #5
47.357 / 61.0

# Verdict Execution time Memory Grader output
1 Partially correct 347 ms 936 KB Partially correct
2 Partially correct 340 ms 936 KB Partially correct
3 Partially correct 624 ms 684 KB Partially correct
4 Partially correct 493 ms 684 KB Partially correct
5 Partially correct 463 ms 684 KB Partially correct
6 Partially correct 307 ms 940 KB Partially correct
7 Partially correct 328 ms 684 KB Partially correct
8 Partially correct 1 ms 776 KB Partially correct
9 Partially correct 2 ms 768 KB Partially correct
10 Partially correct 0 ms 768 KB Partially correct
11 Partially correct 365 ms 684 KB Partially correct
12 Partially correct 383 ms 684 KB Partially correct
13 Partially correct 601 ms 684 KB Partially correct
14 Partially correct 530 ms 684 KB Partially correct
15 Partially correct 411 ms 684 KB Partially correct
16 Partially correct 302 ms 688 KB Partially correct
17 Partially correct 440 ms 684 KB Partially correct
18 Partially correct 310 ms 940 KB Partially correct
19 Partially correct 314 ms 1272 KB Partially correct
20 Partially correct 286 ms 684 KB Partially correct
21 Partially correct 40 ms 768 KB Partially correct
22 Partially correct 42 ms 764 KB Partially correct
23 Partially correct 60 ms 684 KB Partially correct
24 Partially correct 2 ms 768 KB Partially correct
25 Partially correct 3 ms 768 KB Partially correct
26 Partially correct 2 ms 768 KB Partially correct
27 Partially correct 1 ms 776 KB Partially correct
28 Partially correct 0 ms 768 KB Partially correct
29 Partially correct 364 ms 684 KB Partially correct
30 Partially correct 339 ms 684 KB Partially correct
31 Partially correct 345 ms 684 KB Partially correct
32 Partially correct 330 ms 684 KB Partially correct
33 Partially correct 370 ms 684 KB Partially correct
34 Partially correct 240 ms 940 KB Partially correct
35 Partially correct 309 ms 1276 KB Partially correct
36 Partially correct 317 ms 940 KB Partially correct
37 Partially correct 347 ms 1304 KB Partially correct
38 Partially correct 305 ms 1020 KB Partially correct
39 Partially correct 320 ms 772 KB Partially correct
40 Partially correct 362 ms 768 KB Partially correct
41 Partially correct 323 ms 876 KB Partially correct
42 Partially correct 33 ms 768 KB Partially correct
43 Partially correct 60 ms 684 KB Partially correct
44 Partially correct 89 ms 764 KB Partially correct
45 Partially correct 100 ms 684 KB Partially correct
46 Partially correct 182 ms 684 KB Partially correct
47 Partially correct 199 ms 684 KB Partially correct
48 Partially correct 33 ms 996 KB Partially correct
49 Partially correct 28 ms 736 KB Partially correct