A tiny corpus can make two adjacent pairs tie. This lesson shows the stated lexicographic tie-break as an exact deterministic rule.
highlighted = computed this step
A tiny tie corpus
Use a tiny corpus: word ab has frequency 1 and symbols a b; word ac has frequency 1 and symbols a c. Each word contributes one adjacent pair.
ab:ab,ac:ac
The pair counts tie
The pair (a,b) has count 1, and the pair (a,c) also has count 1. Both are maximum counts, so the stated tie policy must decide.
(a,b)=1,(a,c)=1
Lexicographic tie-break
The stated tie-break chooses the lexicographically smallest pair among max counts. Since (a,b) comes before (a,c), the chosen merge is (a,b) to ab with count 1. This is one toy corpus and one deterministic tie policy; it is not a claim about learned meaning, better tokenization, every tokenizer implementation, or probabilistic behavior.