message: Avoid error on submitting empty lines
diff: @@ -89,6 +89,7 @@ exports.challengesWithCodeSnippet = () => async (req, res, next) => {
  export const getVerdict = (vulnLines: number[], selectedLines: number[]) => {
  let verdict: boolean = true
  + if(selectedLines === undefined) return false
  vulnLines.sort((a, b) => a - b)
  selectedLines.sort((a, b) => a - b)
  if (vulnLines.length !== selectedLines.length) {
  