左旋转字符串
左旋转字符串
http://www.nowcoder.com/questionTerminal/12d959b108cb42b1ab72cef4d36af5ec
public class Solution {
public String LeftRotateString(String str,int n) {
if(str==null||str.length()<n){
return str;
}
StringBuilder sb = new StringBuilder();
//左移几位,就抽取一个长度为几的字符串
String substring = str.substring(0, n);
String substring1 = str.substring(n, str.length());
//将字符串进行拼接,因为是左移,就把后面的字符串放到前面,将要移到的字符串放后面
sb.append(substring1);
sb.append(substring);
return sb.toString();
}
}