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  1. import java.util.ArrayList;
  2. import java.util.List;
  3.  
  4. public class OddEvenTreeHard {
  5.  
  6.     int[] col;
  7.     boolean bad;
  8.  
  9.     void dfs(int cur, int to, String[] dist)
  10.     {
  11.         if(col[cur] == -1)
  12.         {
  13.             col[cur] = to;
  14.         }
  15.         else
  16.         {
  17.             if(col[cur] != to) {
  18.                 bad = true;
  19.             }
  20.             return;
  21.         }
  22.         for(int i = 0; i < dist.length; i++)
  23.         {
  24.             if(dist[cur].charAt(i) == 'E' || dist[i].charAt(cur) == 'E')
  25.                 dfs(i, to, dist);
  26.             if(dist[cur].charAt(i) == 'O' || dist[i].charAt(cur) == 'O')
  27.                 dfs(i, 1-to, dist);
  28.         }
  29.     }
  30.  
  31.     public int[] getTree(String[] dist)
  32.     {
  33.         int[] noSolution = new int[1];
  34.         noSolution[0] = -1;
  35.  
  36.         int n = dist.length;
  37.         col = new int[n];
  38.         bad = false;
  39.  
  40.         int currentCol = 0;
  41.         for(int i = 0; i < n; i++)
  42.             col[i] = -1;
  43.         for(int i = 0; i < n; i++)
  44.             if(col[i] == -1)
  45.             {
  46.                 dfs(i, currentCol, dist);
  47.                 currentCol = 1 - currentCol;
  48.             }
  49.  
  50.         List<Integer> part0 = new ArrayList<Integer>();
  51.         List<Integer> part1 = new ArrayList<Integer>();
  52.         if(bad)
  53.             return noSolution;
  54.         for(int i = 0; i < n; i++)
  55.             if(col[i] == 0)
  56.                 part0.add(i);
  57.             else
  58.                 part1.add(i);
  59.  
  60.         if(part0.size() == 0 || part1.size() == 0)
  61.             return noSolution;
  62.  
  63.         int[] ret = new int[(n-1)*2];
  64.         int p = 0;
  65.         for(int i = 0; i < part1.size(); i++)
  66.         {
  67.             ret[p] = part0.get(0);
  68.             p ++;
  69.             ret[p] = part1.get(i);
  70.             p ++;
  71.         }
  72.         for(int i = 1; i < part0.size(); i++)
  73.         {
  74.             ret[p] = part0.get(i);
  75.             p ++;
  76.             ret[p] = part1.get(0);
  77.             p ++;
  78.         }
  79.         return ret;
  80.     }
  81. }
  82.  
Compilation error #stdin compilation error #stdout 0s 0KB
comments (?)
stdin 
Standard input is empty
compilation info 
Main.java:4: error: class OddEvenTreeHard is public, should be declared in a file named OddEvenTreeHard.java
public class OddEvenTreeHard {
       ^
1 error
stdout 
Standard output is empty
https://ideone.com/rxEUcR
language:
Java (HotSpot 12)
created:
9 years ago
visibility:
secret

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