Wormhole Calc vs Missing Digits

The rules are simple. Fill in the blanks with numbers from 0 to 9 so that multiplication and division can be completed. * However, 0 is not entered in the leftmost cell. Questions are generated each time by the app program. The positions of the holes are determined at random. The last 50 questions created are automatically saved, and you can select and play them again later. Equipped with a memo function, undo and redo, and a lock function for entered numbers, making it easier to organize ideas. Please try once.

Guessing won't fill the blanks. Logic will. Follow the carry from the ones column, and every hidden digit narrows to a single answer. Missing-digit arithmetic and classic cryptarithms, written in chalk on a quiet blackboard. ■ Your first puzzle Your first puzzle walks you through it, one column at a time. No need to know the rules. Replay it anytime from How to Play in Settings. ■ Missing digits Part of a written sum is hidden. Fill in the blanks so the arithmetic works. • Easy: column addition • Normal: addition and single-digit multiplication, chosen so you have to reason, not just subtract • Hard: long multiplication with partial products • Oni: 4×3-digit and 5×2-digit long multiplication Puzzles are generated on your device, so you never run out. ■ Cryptarithms Letters stand for digits, as in SEND + MORE = MONEY. Same letter, same digit; different letters, different digits. 119 puzzles built from everyday English words. ■ Exactly one answer Each puzzle starts as a completed sum, and digits are hidden only while a single answer remains. Every cryptarithm was chosen because it has one solution. ■ Today's puzzle and ranks One puzzle a day, the same for everyone. Weekdays are Normal; weekends are Hard long multiplication. Earn points as you solve and climb from 10th Kyu to Master. Your rank shows as a badge, and every solved day gets a gold stamp on the calendar. ■ Quiet help • Columns that can't work out are gently tinted (you can turn this off) • If you're truly stuck, a hint reveals a single cell ■ Chalk and blackboard Deep green board, chalk-white digits, set vertically the way you'd write by hand. When you solve it, chalk dust drifts up and the board lights up gold. Prefer it plain? Switch to the Simple look in Settings. On iPhone and iPad, the board grows to fit your screen. ■ Great for • Sudoku and crossword fans who want puzzles that actually use arithmetic • Anyone who'd rather deduce than drill • Kids preparing for entrance exams, and their parents • Building a small daily brain-training habit • Playing on planes and trains with no signal ■ Privacy • No account required • Your records stay on this device • Puzzles are created inside the app; no connection needed to play • No tracking and no third-party ads • To show other apps by the same developer, the app reads public App Store listings only. None of your data is sent