Cryptarithms (Alphametics) **Mobile Friendly version**! Personal remix to make it easier for me to solve them. An Error sound plays when you try to assign a Letter to a Digit that is already assigned to another letter, or you try to assign Zero to the first Letter of any Row! FYI - I've solved all 21 puzzles (includes 8 extra ones). Instructions below unchanged from the original project: A type of Verbal Arithmetic puzzle in which a set of words is written down in the form of a long addition sum or some other mathematical problem. The object is to replace the letters of the alphabet with decimal digits to make a valid arithmetic sum. Every different letter, corresponds to a different digit. The left-most digits cannot be zeroes. Solving a cryptarithm involves a mix of deductions and tests of possibilities. The puzzle to be solved is on the left. The lists of possibilities are on the right. Clicking on a possibility once, marks it with a slash. Use this state to mark it as a possibility ruled-out. Clicking a second time, removes the slash and circles the digit. This means you have chosen the digit as the correct substitution (clicking again removes selection). Currently 13 puzzles + 8 added by me (@gregatku).
Thanks to @grandpasp for finding and creating a Scratch version of this interesting and challenging old school (one observed example dates all the way back to 1864) pencil & paper puzzle. See more info in the Wikipedia article "Verbal Arithmetic", from where @grandpasp sourced Puzzle 1. He sourced the others from puzzles-to-print.com (created by Kim White Steel). I added Puzzle 2 from the same Wikipedia article. I also added puzzles 16-18, which were in a book called "150 Puzzles In Crypt-Arithmetic" by Maxey Brooke. The last 2 of which are Number Facts, where the Letters in the crypt form numbers in Words, and the word equation is a mathematical fact. There were other puzzles of this nature in the book, but they had multiple solutions, so I did not include them. However I later found 3 more such puzzles in the "Cryptarithms" link in the External References section of the previously mentioned Wikipedia article. They are puzzles 19-21 and only have 1 solution & they're real "killers" (extremely difficult to solve). So if you have 3 or more serious attempts at solving any one of them, you will be given a clue, namely the correct value of the letter E (being the most common letter in each of these puzzles). That should make them no more difficult to solve than any of the Hard puzzles, possibly even a bit easier. Later I found another one I really liked, which I added as the last of the Easy ones (puzzle 9). I found it online at dcode.fr/cryptarithm-solver. I made a simple costume change to better highlight the selected Digit for a Letter & added code to prevent a Letter being set to a Digit whose value was already assigned to another Letter. It was originally intended to only share it temporarily for only, to help him "improve" his originally released version. Although he took up my suggestion to prevent assignment of a Digit value to more than one Letter, he chose to do it a completely different way to my suggested method. Because I found his way a little confusing to use, I decided to make this remix permanent so I could use this version when trying to solve the puzzles. Given that I was sharing it permanently, I also made a few other colour changes to emphasise that this version is not simply a plagiarised copy. No functional changes. I have since retrofitted his additional puzzles, and the difficulty ratings he gave them, but given that I was able to solve a few of the so called "Hard" puzzles without too much difficulty, I've changed their Difficulty Rating to "Medium" and re-ordered the puzzles accordingly. I also changed the Prev & Next Level button code so they're both permanently displayed, with Prev on puzzle 1 jumping to the last puzzle, and Next on the last puzzle jumping back to the 1st puzzle. Then I decided to change the code for determining if a puzzle is solved or not, by doing the sums in exactly the same way we do when we're solving them, so there are no clues to any solutions inside the project! Then I found it hard to play on my Mobile Phone, so I moved everything over to the left a bit to enable me to make the selection boxes on the right bigger, so contact with them is more easily registered on Mobile Phones. Works much better on my Mobile phone now. However, it annoyed me that I could click on the bottom of a hitbox and it wouldn't register as a hit, so I made them square, but then I could click on a corner of a hitbox and that wouldn't register a hit either. So I made the hitboxes all circles. All good now. I also added a nice graphic effect for when you solve a puzzle. Finally, I added Code to prevent you setting any Leading Letter (1st letter in a Row of the equation) to Zero. Hope you like my changes.
