效绵鼎 Statement of the CFL Pumping Lemma For every context-free language L There is an integer n,such that For every string z in L of length >n There exists z uvwxy such that: 1. wwx≤n. 2 vx>0. 3.For all i>0,uv'wx'y is in L 4Statement of the CFL Pumping Lemma For every context-free language L There is an integer n, such that For every string z in L of length > n There exists z = uvwxy such that: 1. |vwx| < n. 2. |vx| > 0. 3. For all i > 0, uviwxiy is in L. 4