for(var key in arr){
console.log("hello,"+arr[key])
};
for(var key in arr){
arr.reverse()
console.log("hello,"+arr[key])
};
var n = 3;
while (n > 0) {
n=n-1;
arr.reverse();
console.log("Hello,"+ arr[n])
} ;
var n = -1;
while (n<2) {
n=n+1;
console.log("Hello,"+ arr[n])
}
zhang-博文
for(var key in arr){ console.log("hello,"+arr[key]) }; for(var key in arr){ arr.reverse() console.log("hello,"+arr[key]) }; var n = 3; while (n > 0) { n=n-1; arr.reverse(); console.log("Hello,"+ arr[n]) } ; var n = -1; while (n<2) { n=n+1; console.log("Hello,"+ arr[n]) }