Cryptic Math Equation (Backtracking)
Explore how to solve a cryptic math equation by assigning unique digits to letters using backtracking. Learn to implement a recursive algorithm in Ruby that efficiently checks combinations and enforces puzzle constraints to find valid solutions.
Problem
We want to solve this cryptic equation. Each letter stands for a unique digit (0–9). There are no leading zeros. Write a program that finds a numeric assignment to the letters for which the given equation is satisfied.
UKUSA+ USSR--------AGING
Cryptic equation example
Purpose
Backtracking to solve number puzzles
Analyze
The brute-force approach by nesting loops will work for this puzzle, but won’t be elegant. We could use backtracking to solve this puzzle ...