配列の置き換え基礎 途中！

これをfor文で書き直さないと駄目なのですが、その前に一文づつコードで書いて見ました。


import java.io.*;

public class hairetu_1 {
public static void main(String[] args) throws IOException
{
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

String[] hairetu = new String[3];

String str = br.readLine();
String num = str;
hairetu[0] = num;

hairetu[1] = "none ";
hairetu[2] = "none ";

System.out.print(hairetu[0] + hairetu[1] + hairetu[2]);

hairetu[1] = hairetu[0];

String str2 = br.readLine();
String num2 = str2;
hairetu[0] = num2;

System.out.print("¥n");
System.out.print(hairetu[0] + hairetu[1] + hairetu[2]);

hairetu[2] = hairetu[1];
hairetu[1] = hairetu[0];


String str3 = br.readLine();
String num3 = str3;
hairetu[0] = num3;

System.out.print("¥n");
System.out.print(hairetu[0] + hairetu[1] + hairetu[2]);
}
}

結果表示は

3none none 4

43none 5

543

なので初歩的な書き方は出来るんですよね！

他のforにネストする時迷うのは何故でしょう.....