[{
  "exerciseType": "GRAMMAR",
  "totalTrueCases": 3,
  "totalFalseCases": 1,
  "containLetters": ["a", "b"],
  "randomStringLength": [0, 15],
  "description": "Write a grammar for the alphabet $\\Sigma = \\{a, b\\}$ and language $L = \\{b, ab, bab\\}$.",
  "testCases": [
    {
      "b": true,
      "ShowTestCase":true
    },
    {
      "ab": true,
      "ShowTestCase":true
    },
    {
      "bab": true,
      "ShowTestCase":true
    },
    {
      "": false,
      "ShowTestCase":true
    },
    {
      "aaa": false,
      "ShowTestCase":false
    },
    {
      "bbb": false,
      "ShowTestCase":false
    },
    {
      "abba": false,
      "ShowTestCase":false
    }
  ],
  "solution":
  [{
    "S": "b"
  },
   {
     "S": "ab"
   },
   {
     "S": "bab"
   }
  ]
}]