oj.uz

Submission #1079200

# Submission time Handle Problem Language Result Execution time Memory
1079200 2024-08-28T11:58:04 Z anango Stations (IOI20_stations) C++17
10 / 100
 2174 ms 4792 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) {
	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]+1;
        }
        else {
            labels[i] = 1000+tout[i]+1;
        }
        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>1000) {
        t-=1000;
    }
    if (s>1000) {
        //depth is even
        s-=1000;
        //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);
        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]-=1000;
        }
        //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());
        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]+1000;
            }
        }
        return c.back()+1000;
    }
	return c[0];
}

Compilation message

stations.cpp: In function 'int find_next_station(int, int, std::vector<int>)':
stations.cpp:81:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   81 |         for (int i=2; i<c.size(); i++) {
      |                       ~^~~~~~~~~
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=0; i<c.size(); i++) {
      |                       ~^~~~~~~~~

Subtask #1
0 / 5.0

# Verdict Execution time Memory Grader output
1 Incorrect 40 ms 600 KB Invalid labels (values out of range). scenario=0, k=1000, vertex=0, label=1020
2 Halted 0 ms 0 KB -

Subtask #2
0 / 8.0

# Verdict Execution time Memory Grader output
1 Incorrect 80 ms 684 KB Invalid labels (values out of range). scenario=0, k=1000, vertex=0, label=2992
2 Halted 0 ms 0 KB -

Subtask #3
0 / 16.0

# Verdict Execution time Memory Grader output
1 Incorrect 1239 ms 3580 KB Wrong query response.
2 Halted 0 ms 0 KB -

Subtask #4
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 2133 ms 4696 KB Output is correct
2 Correct 1694 ms 4264 KB Output is correct
3 Correct 1577 ms 3840 KB Output is correct
4 Correct 5 ms 764 KB Output is correct
5 Correct 7 ms 768 KB Output is correct
6 Correct 1 ms 776 KB Output is correct
7 Correct 1452 ms 3372 KB Output is correct
8 Correct 2174 ms 4792 KB Output is correct
9 Correct 1738 ms 3984 KB Output is correct
10 Correct 1519 ms 3624 KB Output is correct
11 Correct 9 ms 768 KB Output is correct
12 Correct 13 ms 768 KB Output is correct
13 Correct 8 ms 872 KB Output is correct
14 Correct 8 ms 1024 KB Output is correct
15 Correct 2 ms 772 KB Output is correct
16 Correct 1384 ms 3276 KB Output is correct
17 Correct 1495 ms 3136 KB Output is correct
18 Correct 1362 ms 3320 KB Output is correct
19 Correct 1269 ms 3164 KB Output is correct
20 Correct 1384 ms 3316 KB Output is correct

Subtask #5
0 / 61.0

# Verdict Execution time Memory Grader output
1 Incorrect 1213 ms 3640 KB Wrong query response.
2 Halted 0 ms 0 KB -