05.反转数组

 

5.反转数组

 

var arr = [1,2,3,4,5,6,7,8];
for(let i = 0;i<arr.length/2;i++){
    //arr[0]    arr[arr.length-1-0];
    //arr[1]    arr[arr.length-1-1];
    //arr[2]    arr[arr.length-1-2];
    //arr[3]    arr[arr.length-1-3];
    
    //借助第三方变量交换两个变量的值
    //var temp = arr[i];
    //arr[i] = arr[arr.length-1-i];
    //arr[arr.length-1-i] = temp;
     [arr[i],arr[arr.length-1-i]]=[arr[arr.length-1-i],arr[i]]
}
console.log(arr);