题解 | #排序# 归并排序

/**
 * 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
 *
 * 将给定数组排序
 * @param arr int整型一维数组 待排序的数组
 * @return int整型一维数组
 */
function MySort( arr ) {
   if(arr.length < 2) return arr;
   const middle = Math.floor(arr.length / 2);
   const left = arr.slice(0,middle);
   const right = arr.slice(middle);
   return mergeSort(MySort(left),MySort(right)); 
}
function mergeSort(left,right){
    const result = [];
    while(left.length && right.length){
        if(left[0] <= right[0]){
            result.push(left.shift());
        }else{
            result.push(right.shift());
        }
    }
    while(left.length){
        result.push(left.shift());
    }
    while(right.length){
        result.push(right.shift());
    }
    return result;
}
module.exports = {
    MySort : MySort
};