Formal Statement
If a language L is context-free, then there exists some integer p ≥ 1 such that any string s in L with |s| ≥ p (where p is a "pumping length") can be written as
- s = uvxyz
with substrings u, v, x, y and z, such that
- 1. |vxy| ≤ p,
- 2. |vy| ≥ 1, and
- 3. uv nxy nz is in L for all n ≥ 0.
Read more about this topic: Pumping Lemma For Context-free Languages
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