1.获取一个字符串的所有组合,如:ABC,有ABC,ACB,BAC,BCA,CAB,CBA,如果考虑单个字符或少于字符串长度的组合则还有,A,B,C,AB,AC,BC,BA,CA,CB.2.代码public class StringPermutations<T> {
public static Set permSet = new TreeSet<>();
public static void permutation(String input){
permutation("",input);
}
private static void pe