A LAMBDA Word Search Puzzle

I've created a 15x10 Word Search. I've included a word list (dynamic range) containing words which might be found in the word search. The goal is to then extract those words when they appear in the...

LAMBDA Word Search Puzzle.xlsx24 KB

excel

office 365

SergeiBaklan

Jul 16, 2022

Patrick2788

Here is one more variant

//------ variant without TEXTJOIN()

reverseColumns=
LAMBDA( data,
    LET(
        n, COLUMNS( data ),
        CHOOSECOLS( data, SEQUENCE(n,,n,-1) )
    ));

reversedText=
LAMBDA( str,
    LET(
        head, LEFT(str),
        tail, RIGHT(str, LEN(str) - 1),
        IF(str = "", "", reversedText(tail) & head)
    ));

isPolindrom=
LAMBDA( text, text = reversedText( text ) );

checkSingleWord=
LAMBDA( str, vector,
    LET(
        getWord, REDUCE("", vector,
            LAMBDA( a,v,
                IF( LEFT(str, LEN(a&v)) = a&v, a&v,
                IF( LEFT(str) = a, v,
                    IF( a = str, a, "" )
                ) ) ) ),
        IF( getWord = str, str, "")
    ));

checkListOfWords=
LAMBDA( wordsVector, vector,
    LET(
        getWords,
            REDUCE("", wordsVector,
                LAMBDA(a,v, VSTACK(a, checkSingleWord( v, vector) ) )
            ),
        IFERROR( FILTER( getWords, getWords <> ""), "" )
    ));

wordsInMatrix=
LAMBDA( data, wordsVector,
    LET(
        k, SEQUENCE( ROWS(data) ),
        scanData, REDUCE(1, k,
            LAMBDA(a,v,
                CHOOSECOLS(
                    IF( v < SEQUENCE(,v,v,-1),
                        a,
                        VSTACK(a, checkListOfWords( Words, CHOOSEROWS(data,v) ) ) ),
                1 )
            )),
        removeFirst, DROP( scanData, 1 ),
        FILTER( removeFirst, removeFirst <> "")
));

wordsInPuzzle=
LAMBDA( data, wordsVector,
    LET(
    allWords, SORT( VSTACK(
        wordsInMatrix( data, wordsVector ),
        wordsInMatrix( reverseColumns( data ), wordsVector ),
        wordsInMatrix( TRANSPOSE( data ), wordsVector ),
        wordsInMatrix( reverseColumns( TRANSPOSE( data ) ), wordsVector )
    )),
    ifPolindroms, MAP(allWords, LAMBDA(v, isPolindrom(v) ) ),
    polindroms, UNIQUE( FILTER(allWords, ifPolindroms)),
    notPolindroms, FILTER(allWords, ifPolindroms -1),
    stack, IF( ISERR(polindroms), notPolindroms, VSTACK( polindroms, notPolindroms ) ),
    SORT( stack )
));

LAMBDA Word Search Puzzle.xlsx22 KB

PeterBartholomew1

Silver Contributor

Jul 21, 2022

Patrick2788

Rather than listing the words found, I have identified them on copies of the puzzle.

Worksheet formula
= Solveλ(Puzzle, WordList, 0) +
  Solveλ(Puzzle, WordList, 1)

Solveλ = LAMBDA(grid, findlist, d,
    LET(
        puzzleStr,      Grid2Stringλ(grid,d),
        extendedList,   VSTACK(findlist, MAP(findlist, Reverseλ)),
        pointer,        MAP(extendedList, LocateWordλ(puzzleStr)),
        ptr,            FILTER(pointer,pointer),
        wLen,           FILTER(LEN(extendedList),pointer),
        puzzleIdx,      SEQUENCE(LEN(puzzleStr)),
        n,              IF(d, ROWS(grid), COLUMNS(grid)),
        String2Gridλ(puzzleIdx,ptr,wLen,n,d)
    )
);

Grid2Stringλ = LAMBDA(grid,d,
    LET(
        nRow,           ROWS(grid),
        nCol,           COLUMNS(grid),
        extendedGrid,   EXPAND(grid, nRow+1, nCol+1, "|"),
        CONCAT(TOCOL(extendedGrid,,d))
    )
);

String2Gridλ = LAMBDA(k,wp,wl,n,d,
    LET(
        s, XLOOKUP(k,wp,wp,0,-1),
        ℓ, XLOOKUP(k,wp,wl,0,-1),
        b, SIGN(k+1-s <= ℓ),
        ext, IF(d, 
            WRAPCOLS(b,n+1),
            WRAPROWS(b,n+1)),
        DROP(ext,-1,-1)
    )
);

LocateWordλ = LAMBDA(puzzleStr, LAMBDA(word, 
    IFERROR(FIND(word, puzzleStr),0))
);

Reverseλ = LAMBDA(word,
    LET(n, LEN(word), k, SEQUENCE(n, 1, n, -1), CONCAT(MID(word, k, 1)))
);

Something else that occurs to me is that your recursion technique might be the only way forward if the standard across and down wordsearch had words that change direction like a game of 'snake'.

LAMBDA Word Search Puzzle.xlsx22 KB

SergeiBaklan

MVP

Jul 22, 2022

PeterBartholomew1

Nice idea, need to play with it bit more. Do I understood correctly you don't generate "Words found in puzzle" ?

PeterBartholomew1
Silver Contributor
Jul 22, 2022
True. For each word, I record where it occurs (pointer/ptr) and how many characters it occupies (wLen). I do not need to store the word itself, though that would be easier than identifying its location within the grid.

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A LAMBDA Word Search Puzzle

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