素来

给定数组a[1,2,3],用a里面的元素来生成一个长度为5的数组，打印出其排列组合 ruby代码： def all_possible_arr arr, length = 5 ret = [] length.times do if ret.empty? ret = arr....

var myFish = ["angel", "clown", "mandarin", "surgeon"]; //从第 2 位开始删除 0 个元素，插入 "drum" var removed = myFish.splice(2, 0, "drum"); //运算后的 myFish:["angel", "clown", "drum", "mandarin"...