java 使用if將String內字符轉換 遞歸

下面有壹個非遞歸的，如果是遞歸的話可能需要改接口（example函數的參數）。

{

public?static?String?exampleD(String?s)

{

int?length?=?s.length?();

String?news="";

for(int?i?=0;i<length;i++)

{

char?ch?=?s.charAt(i);

news+=?swap(ch);

}

return?news;

}

private?static?char?swap(char?ch)

{

if(ch=='A')

return?'T';

else?if(ch?==?'T')

return?'A';

else?if(ch?==?'G')

return?'C';

else?if(ch?==?'C')

return?'G';

else

return?'?';

}

public?static?void?main(String[]?args)

{

String?s;

Scanner?input?=?new?Scanner(System.in);

s?=?input.nextLine();

String?news?=?exampleD(s);

System.out.println(s+"--->"+news);

input.close();

}

}