Finding CFG Example

Example

With Alphabet $\Sigma =\{0,1\}$ With Language $L=\{x\in {\Sigma }^{\ast }:{\#}_0(x)={\#}_1(x)\}$ The CFG that generates $L$ is:

$$\begin{array}{r}S\to 0A,1B,ϵ\\ A\to 1S,0AA\\ B\to 0S,1BB\end{array}$$

Alternate CFG

$$S\to ϵ,0S1S,1S0S$$