Solve the following cryptarithmetic problem by hand, using the strategy of backtracking with forward checking, most constrained variable, and least-constraining-value heuristics.
State the variables, values, and constraints at each step.
Solve the following cryptarithmetic problem by hand, using the strategy of backtracking with forward checking, most constrained variable, and least-constraining-value heuristics.
T W O
+ T W O
F O U R
(a)
(b)