Solution
= Solution
This language is context-free. One grammar is
$$
S\to aSc\mid aTc,\qquad T\to bT\mid b,
$$
which independently chooses at least one outer $a,c$ pair and at least one $b$.
= Solution
This language is context-free. One grammar is
$$
S\to aSc\mid aTc,\qquad T\to bT\mid b,
$$
which independently chooses at least one outer $a,c$ pair and at least one $b$.