[KissLick]

Ciao guys,

I'd like to ask you if you know about any way, how to clone/copy trie structure.
I have a adt trie which I need to copy (like create a new branch) and modify both the original and copied tries separately.

[Spirit_12]

Where are you trying to clone it? Website ?

[KissLick]

This trie in plugin.

[Powerlord]

I don't think its possible in SourceMod 1.6.

In 1.7 it IS possible. This example assumes that all of the tries value types are the same. It also does deep copies of strings and arrays (if the arrays are simple values) if those are the type of value in the trie.

PHP Code:

enum TrieValueType
{
    TrieValue_Value,
    TrieValue_String,
    TrieValue_Array,
}

stock Handle:CloneTrie(Handle:oldTrie, TrieValueType:valueType=TrieValue_Value, valueLength=0)
{
    new Handle:newTrie = CreateTrie();
    
    new Handle:snapshot = CreateTrieSnapshot(oldTrie);
    
    new itemCount = TrieSnapshotLength(snapshot);
    
    for (new i = 0; i < itemCount; i++)
    {
        new length = TrieSnapshotKeyBufferSize(snapshot, i);
        
        new String:key[length];
        GetTrieSnapshotKey(snapshot, i, key, length);
        switch(valueType)
        {
            case TrieValue_Value:
            {
                new value;
                if (GetTrieValue(oldTrie, key, value))
                {
                    SetTrieValue(newTrie, key, value);
                }
            }
            
            case TrieValue_String:
            {
                new String:value[valueLength];
                if (GetTrieString(oldTrie, key, value, valueLength))
                {
                    new String:newValue[valueLength];
                    strcopy(newValue, valueLength, value);
                    
                    SetTrieString(newTrie, key, newValue);
                }
            }
            
            case TrieValue_Array:
            {
                new valueArray[valueLength];
                if (GetTrieArray(oldTrie, key, valueArray, valueLength))
                {
                    new newValueArray[valueLength];
                    for (new j = 0; j < valueLength; j++)
                    {
                        newValueArray[j] = valueArray[j];
                    }
                    SetTrieArray(newTrie, key, newValueArray, valueLength);
                }
            }
        }
        
    }
    
    return newTrie;
} 


Usage is:

// For a trie of Values
new Handle:newTrie = CloneTrie(oldTrie);

// For a trie of Strings, where the last arg is the string length
new Handle:newTrie = CloneTrie(oldTrie, TrieValue_String, 32);

// For a trie of Arrays, where the last arg is the array length
new Handle:newTrie = CloneTrie(oldTrie, TrieValue_Array, 32);

[KissLick]

Yep... Unfortunately I am using SM 1.6 (might consider to use newer version) :-( Thx Powerlord

[Miu]

couldn't you just store the keys (or w/e information it is you're missing in 1.6) in a separate array when you set stuff in the trie?

[KissLick]

That would work, but I already found a way, how to work around cloning trie in my algorithm.

[Drixevel]

enum TrieValueType
{
	TrieValue_Value,
	TrieValue_String,
	TrieValue_Array,
}

stock Handle CloneTrie(Handle oldTrie, TrieValueType valueType = TrieValue_Value, int valueLength = 0)
{
	Handle newTrie = CreateTrie();
	Handle snapshot = CreateTrieSnapshot(oldTrie);
	
	int itemCount = TrieSnapshotLength(snapshot);
	
	for (int i = 0; i < itemCount; i++)
	{
		int length = TrieSnapshotKeyBufferSize(snapshot, i);
		
		char[] key = new char[length];
		GetTrieSnapshotKey(snapshot, i, key, length);
		switch(valueType)
		{
		case TrieValue_Value:
			{
				int value;
				if (GetTrieValue(oldTrie, key, value))
				{
					SetTrieValue(newTrie, key, value);
				}
			}
			
		case TrieValue_String:
			{
				char[] value = new char[valueLength];
				if (GetTrieString(oldTrie, key, value, valueLength))
				{
					char[] newValue = new char[valueLength];
					strcopy(newValue, valueLength, value);
					
					SetTrieString(newTrie, key, newValue);
				}
			}
			
		case TrieValue_Array:
			{
				int[] valueArray = new int[valueLength];
				if (GetTrieArray(oldTrie, key, valueArray, valueLength))
				{
					int newValueArray[valueLength];
					for (int j = 0; j < valueLength; j++)
					{
						newValueArray[j] = valueArray[j];
					}
					SetTrieArray(newTrie, key, newValueArray, valueLength);
				}
			}
		}
		
	}
	
	return newTrie;
}