text: function sum(a, b){
      let [sI1 , sF1=''] = a.split('.');
      let [sI2 , sF2=''] = b.split('.');
  
      sI1 = sI1.split('').map((item) => parseInt(item)).reverse();
      sI2 = sI2.split('').map((item) => parseInt(item)).reverse();
  
      if (sF1.length + sF2.length === 0) {
          return sumInterger(sI1, sI2);
      }
  
      sF1 = sF1.split('').map((item) => parseInt(item));
      sF2 = sF2.split('').map((item) => parseInt(item));
  
      return sumInterger(sI1, sI2) + '.' + sumInterger(sF1, sF2, true);
  }
  
  function sumInterger(sI1, sI2, isFloat) {
      let s1 = [];
      let sIIndex = 0;
      let Junit = 0;
      
      while (sI1.length > sIIndex && sI2.length > sIIndex) {
          let twoISum = sI1[sIIndex] + sI2[sIIndex] + Junit;
          Junit = 0;
          if (twoISum >= 10) {
              s1.push(twoISum - 10);
              Junit = 1;
          } else {
              s1.push(twoISum);
          }
          sIIndex++;
      }
      if (sI1.length > sIIndex) {
          for (let i = sIIndex; i < sI1.length; i++) {
              s1.push(sI1[i] + Junit);
              Junit = 0;
          }
      } else if (sI2.length > sIIndex) {
          for (let i = sIIndex; i < sI2.length; i++) {
              s1.push(sI2[i] + Junit);
              Junit = 0;
          }
      }
      if (isFloat) {
          return s1.join('');
      } else {
          return s1.reverse().join('');
      }
      
  }
  
  console.log(sum('12345.123456789', '234.123456789'));
  
  function upsetPoker() {
       let result = [];
       let origin = [];
       for (let i = 0 ; i < 54 ; i++) {
          origin.push(i);
       }
      //  for (let i = 0; i < 54; i++) {
      //      origin.push(i);
      //      const random = parseInt(Math.random()*(54-i));
      //      const deleteNum = origin[random];
      //      origin.splice(random,1);
      //      result.push(deleteNum);
      //  }
  
       for (let i = 53; i > 0; i--) {
           const random = parseInt(Math.random()*i);
           const index = origin[random]; // 取出一个随机数
           result.push(origin[index]); // 存进数组
           origin[index] = origin[i]; // 把已使用的数据换了
       }
  
       return result;
  }
  
  console.warn(upsetPoker())
  
  function sort(nums) {
      if (nums.length <= 1) return nums;
      const middle = parseInt(nums.length / 2);
      let leftNums = nums.slice(0,middle);
      let rightNums = nums.slice(middle);
      return merge(sort(leftNums), sort(rightNums));
  }
  
  function merge(leftNums, rightNums) {
      let i = 0;
      let j = 0;
      const result = []
      while (i < leftNums.length && j < rightNums.length) {
          if (leftNums[i] < rightNums[j]) {
              result.push(leftNums[i]);
              i++;
          } else {
              result.push(rightNums[j]);
              j++;
          }
      }
      if (i < leftNums.length-1) result.push(leftNums.slice(i)); 
      if (j < rightNums.length-1) result.push(rightNums.slice(j)); 
      return result;
  }
  
  class Person {
      getName() {
          let a = 1;
          setTimeout(function(){
              console.log(a);
          }, 0)
      }
  }
  
  const person = new Person();
  person.getName();