What are alphametics?
Alphametics are cryptarithms that spell out words. Given a mathematical expression, every digit in the expression is replaced by a letter. One of the most famous alphametics, spelling out ‘SEND MORE MONEY’ appears above. This alphametic was first published by Henry Dudeney, a British puzzlist, in 1924.
Five rules govern alphametics:
- Identical digits are replaced by the same letter. Different digits are replaced by different letters.
- After replacing all the letters with digits, the resulting arithmetic expression must be mathematically correct.
- Numbers cannot start with 0. For example, the number 0900 is illegal.
- Each problem must have exactly one solution, unless stated otherwise (unlike the “Hindu” problems where there might be no solution or multiple solutions).
- The problems will be in base 10 unless otherwise specified. This means that the letters replace some or all of the 10 digits – 0, 1, 2, 3, 4, 5, 6, 7, 8, 9.
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