题解 | #数组中出现次数超过一半的数字#

{
    // write code here
    //reduce() 方法接收一个函数作为累加器
    let result = numbers.reduce((temp,data) => {
        temp[data] = temp[data] ? temp[data] + 1 : 1;
        return temp;
    },{})
    let num;
    for(let index in result){
        if(result[index] > numbers.length/2){
            num = index;
        }
    }
    return num;
}
module.exports = {
    MoreThanHalfNum_Solution : MoreThanHalfNum_Solution
};

//排序解法
function MoreThanHalfNum_Solution(numbers)
{
   numbers = numbers.sort((a,b) => a-b);
   let middle = numbers[Math.floor(numbers.length / 2)];
   let count = 0;
   numbers.forEach(value => {
       if(value === middle){
           count++;
       }
   })
    return (count > numbers.length / 2) ? middle : 0;
}

module.exports = {
    MoreThanHalfNum_Solution : MoreThanHalfNum_Solution
};

// 对象解法
function MoreThanHalfNum_Solution(numbers)
{
    let len = Math.floor(numbers.length / 2);
    let obj = {};
    for(let i = 0; i < numbers.length; i++){
        if(obj[numbers[i]]){
            obj[numbers[i]]++;
        }else{
            obj[numbers[i]] = 1;
        }
    }
    for(let k in obj){
        if(obj[k] > len){
            return k;
        }
    }
    return 0;
}
module.exports = {
    MoreThanHalfNum_Solution : MoreThanHalfNum_Solution
};