text: module.exports = function zeros(expression) {
    let numbers = expression.split("*");
    let num;
    let result = [];
    let count;
    let countZeros = 0;
  
    for(let i = 0; i < numbers.length;i++){
      if(numbers[i].slice(-2) == "!!"){
        num = BigInt(numbers[i].slice(0,-2));
        count = BigInt(2);   
      }
      else {
        num = BigInt(numbers[i].slice(0,-1));
        count = BigInt(1);
      }
      result[i] = num;
      num = num - count;
      while(num >= 1){
        result[i] *= num;
        num -= count;
      }
    }
    let res = BigInt(1);
    for(let j = 0; j < result.length; j++){
      res *= result[j];
    }
  
    while( res % 10n === 0n){
      res = res / 10n;
      countZeros++;
    }
  
    return countZeros;
  }
  