我有一个字符串数组
{"ted", "williams", "golden", "voice", "radio"}
并且我希望这些关键字的所有可能组合都采用以下形式:
{"ted", "williams", "golden", "voice", "radio", "ted williams", "ted golden", "ted voice", "ted radio", "williams golden", "williams voice", "williams radio", "golden voice", "golden radio", "voice radio", "ted williams golden", "ted williams voice", "ted williams radio", .... }
我已经去了好几个小时了,没有得到有效的结果(高级编程的副作用?)。
我知道解决方案应该很明显,但是老实说,我被卡住了!接受Java / C#解决方案。
编辑 :
编辑2 :查看答案中的链接后,事实证明番石榴用户可以在com.google.common.collect.Sets中使用powerset方法
编辑: 正如FearUs指出的那样,更好的解决方案是使用Guava的Sets.powerset(Set set)。
编辑2: 更新的链接。
此解决方案的快速而肮脏的翻译:
public static void main(String[] args) { List<List<String>> powerSet = new LinkedList<List<String>>(); for (int i = 1; i <= args.length; i++) powerSet.addAll(combination(Arrays.asList(args), i)); System.out.println(powerSet); } public static <T> List<List<T>> combination(List<T> values, int size) { if (0 == size) { return Collections.singletonList(Collections.<T> emptyList()); } if (values.isEmpty()) { return Collections.emptyList(); } List<List<T>> combination = new LinkedList<List<T>>(); T actual = values.iterator().next(); List<T> subSet = new LinkedList<T>(values); subSet.remove(actual); List<List<T>> subSetCombination = combination(subSet, size - 1); for (List<T> set : subSetCombination) { List<T> newSet = new LinkedList<T>(set); newSet.add(0, actual); combination.add(newSet); } combination.addAll(combination(subSet, size)); return combination; }
测试:
$ java PowerSet ted williams golden [[ted], [williams], [golden], [ted, williams], [ted, golden], [williams, golden], [ted, williams, golden]] $