数组中出现次数超过一半的数字

一：
function MoreThanHalfNum_Solution(numbers)
{
  var obj = {};
  var length = numbers.length;
  numbers.forEach(function(d) {
    if (obj[d]) {
      obj[d]++;
    } else {
      obj[d] = 1;
    }
  })
  for (var i in obj) {
    if (obj[i] > Math.floor(length / 2)) {
      return i;
    }
  }
  return 0;
}
二：

function MoreThanHalfNum(arr) {
    arr.sort();
    if(arr.length%2===0){
        console.log(arr[arr.length/2])
    }else {
        console.log(arr[(arr.length-1)/2])
    }
}
var arr=[0,1,2,3,3,3,3];
MoreThanHalfNum(arr);        //3