Arithmetic Word Bash

Solving the cryptarithmetic puzzle in C++

This hard coding problem asks you to verify and enumerate valid letter-to-digit mappings for an arithmetic equation. It is a classic constraint-satisfaction problem that tests your ability to combine permutation search, constraint propagation, and careful validation logic.

The core challenge is to explore the space of all possible digit assignments to unique letters, enforce the no-leading-zeros rule, and verify that the arithmetic constraint (sum of left-side numbers equals the right-side number) holds. A working solution typically uses backtracking with early pruning: assign digits to letters one at a time, check constraints incrementally, and backtrack as soon as a partial assignment becomes infeasible. Efficiency matters here—careless enumeration can time out on larger instances.

• Backtracking and constraint satisfaction
• Permutation generation with pruning
• Leading-zero constraints and their impact on search space
• Arithmetic validation and carry propagation