Theorem $[$Pumping Lemma for Regular Languages$]$:

If $L$ is a regular language, then there is a positive integer $p$ such that for every

string $s$ in $L$ of length at least $p,$ there are strings $x,y,$ and $z$ satisfying the

following:

$s=xyz$

$|xy|p$

$|y|>0$

for every iinN,$x{y}^i$zinL