Machine scheduling Time Limit: 5000/2000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others) Total Submission(s): 1000 Accepted Submission(s): 363 Problem Description A Baidu's engineer needs to analyze and process large amount of data o
排列组合 Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 1736 Accepted Submission(s): 726 Problem Description有n种物品,并且知道每种物品的数量.要求从中选出m件物品的排列数.例如有两种物品A,B,并且数量都是1,从中选2件物品,则排列有"AB","BA&quo
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.map {|i| [i]} else new_ret = [] ret.each do |r| arr.each do |e| new_ret << r.clone.unshift(e) end end ret = new_r