Below are some context-free languages.For each,devise a PDA that accepts the language by empty stack. You may ,if you wish, first construct a grammar for the language, and then convert to a $PDA:$
- $\{a^{n}b^{m}c^{2(n+m)}|n\geq 0,m\geq 0\}$
- $\{a^{i}b^{j}c^{k}|i=2j $(or)$ j=2k\}$
- $\{0^{n}1^{m}|n\leq m\leq 2n\}$
