export function mostFrequentChar(text: string): string {
  let mapper = new Map<string, number>()
  let arrs= text.split('')
  for(let arr of arrs){
    if(mapper.has(arr)){
      mapper = mapper.set(arr, mapper.get(arr)! + 1)
    } else {
      mapper = mapper.set(arr, 1)
    }
  }

 let maxCount = 0
 let maxChar = ''

 for(let [char, count] of mapper){
  if(count > maxCount){
    maxCount = count
    maxChar = char
  }
 }
  return maxChar;
}