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What is the pCrawl variable referring to in Trie code?

Various sites like this one use a pCrawl variable to keep track of where a pointer is in the Trie data structure. I can see why the "crawl" part of the variable makes sense, if this means that the variable is "crawling" around the tree... but what does the p refer to?

An example method: void insert(struct TrieNode *root, string key) { struct TrieNode *pCrawl = root; 

for (int i = 0; i < key.length(); i++) 
{ 
    int index = key[i] - 'a'; 
    if (!pCrawl->children[index]) 
        pCrawl->children[index] = getNode(); 

    pCrawl = pCrawl->children[index]; 
} 

// mark last node as leaf 
pCrawl->isEndOfWord = true;

}

Solution

  • Usually, in C language, a lower case p as a variable name prefix can be interpreted for pointer. This is the case in the example you provided.

    This is in no case an explicit rule, just a naming convention followed here and there.