功课 急用

public class C {    public static void  align(String str,int k,String c){        if(k-str.length() >0){            for(int i=0;i<k-str.length();i++)                str=str+c;        }        System.out.println("左对齐："+str);            System.out.println("右对齐："+new StringBuffer(str).reverse().toString());    }         public static void main(String[] args){        //左对齐和右对齐，参数为一个字符串，和一个整数，还有一个字符。        //当字符串长度小于整数时，用字符补全。        align("abcdefg",20,"*");    }}
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Java code
    public static void main(String[] args) {        String str = "hello";        System.out.println(left(str, 10, '+'));        System.out.println(right(str, 10, '+'));    }    public static String left(String str, int len, char c) {        StringBuffer sb = new StringBuffer(str);        while (sb.length() < len) {            sb.insert(0, c);        }        return sb.toString();    }    public static String right(String str, int len, char c) {        StringBuffer sb = new StringBuffer(str);        while (sb.length() < len) {            sb.append(c);        }        return sb.toString();    }