Challenges : Recursion : Robot collect points

#1

Please tell the mistake.

#2

it gives u tle
refer to this

#3

It is giving wrong answer and not TLE. Also, can you explain your code?

#4

Intuitively, start from every cell and try to build a word in the dictionary. Backtracking (dfs) is the powerful way to exhaust every possible ways. Apparently, we need to do pruning when current character is not in any word.

steps:

  1. make trie for the input string array
     class TrieNode {
          TrieNode[] next = new TrieNode[26];
          String word;
     }
  1. start from 0,0 to m,m do a dfs travesal from each i,j cell
  2. in dfs function update the current character to # so that the current character cannot be used again
    a. check for all 4 positiion i-1, j || i+1, j || i,j+1 || j,j-1
    b. remember to backtrack the position

i hope this explains the code

#5

Ok. Also, close this doubt at your end as even if I close this doubt it gets reopened by itself on page closing or refreshing.

#6

okay, sure …
:slight_smile: