题解 | #左旋转字符串#

import java.lang.*;
public class Solution {
    public String LeftRotateString(String str,int n) {
        if(str==null||str.length()==0) return "";
        if(n==0) return str;
        String tmp =str.substring(0,n);
        str =str.replace(tmp," ");
        str=str+tmp;
        String s=str.substring(1,str.length());
        return s;
    }
}