Grammar -

S -> {A} | {} A -> C:BE B -> C|{A}|[BF] C -> "v" | v F -> ,B | @ E -> ,A | @

Tokens - '[' ',' ']' '{' '}' '"' ':' char int

'{"a":"b"}'

Dictionary -> {KeyValue} | {} json -> {A A -> KeyValue} | } KeyValue -> Key:ValueNextExpr Key -> "char" | int Value -> Const | {Const:ValueNextKeyValue} | [ValueNextValue] NextValue -> ,Value | e NextKeyValue -> ,NextKeyValue | e

KeyValue -> {}