public class Demo11 { public static String LeftRotateString(String str, int k) { if( k <=0 ) { return str; } int offset = k%str.length(); String temp = str+str; int start = str.length()-k; int end = str.length()-1+ (str.length()-k)+1; return temp.substring(start,end); } public static void main(String[] args) { System.out.println(LeftRotateString("abcd", 2)); } } 仅供参考，不知道合不合题意