三种java 去掉字符串中的重复字符函数

三种java 去掉字符串中的重复字符函数

public static void main(string[] args) {
        system.out.println(removerepeatedchar("ddddccffgd"));
    }
    public static string removerepeatedchar(string s) {
        if (s == null)
            return s;
        stringbuilder sb = new stringbuilder();
        int i = 0, len = s.length();
        while (i < len) {
            char c = s.charat(i);
            sb.append(c);
            i++;
            while (i < len && s.charat(i) == c) {
                i++;
            }
        }
        return sb.tostring();
    }

//实例二java去掉重复字符串

private static string removesamestring(string str)   
{   
 set<string> mlinkedset = new linkedhashset<string>();   
 string[] strarray = str.split(" ");   
 stringbuffer sb = new stringbuffer();
 for (int i = 0; i < strarray.length; i++)   
 {   
  if (!mlinkedset.contains(strarray[i]))   
  {   
   mlinkedset.add(strarray[i]);   
   sb.append(strarray[i] + " ");   
  }   
 }   
 system.out.println(mlinkedset);   
 return sb.tostring().substring(0, sb.tostring().length() - 1);   
  }