import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.RandomAccessFile;

public class C14_10 {
    public static void main(String args[]) {
        int num, a;
        long fp;
        try {
            InputStreamReader din = new InputStreamReader(System.in);//键盘输入
            BufferedReader in = new BufferedReader(din);
            
            //建立随机存取文件  
            //RandomAccessFile rf = new RandomAccessFile(args[0], "rw");
            String str = in.readLine();
            RandomAccessFile rf = new RandomAccessFile(str, "rw");
            
            
            System.out.println("请输入五个整数");
            int b[] = new int[5];
            for (int i = 0; i < 5; i++) {
                System.out.print("第" + (i + 1) + "个数   ");
                b[i] = Integer.parseInt(in.readLine());
                rf.writeInt(b[i]); //写入文件
            }
            while (true) {
                fp = 0;
                rf.seek(0); //移动文件指针到文件头
                System.out.print("请输入要显示第几个数（1-5）：");
                num = Integer.parseInt(in.readLine()); //读入序号
                num = num - 1;
                fp = (num) * 4; //每个整数4个字节，计算移动位数
                rf.seek(fp); //移动文件指针到要显示数的首位 
                a = rf.readInt();
                System.out.println("第" + (num + 1) + "个数是: " + a);
                System.out.print("改写此数 ");
                b[num] = Integer.parseInt(in.readLine());
                fp = num * 4;
                rf.seek(fp);
                rf.writeInt(b[num]); //写入文件
                System.out.print("继续吗?(y/n) ");
                if ((in.readLine()).equals("n"))
                    break;
            }
            
            //rf.close();
            in.close();
            din.close();
            
        } catch (Exception E) {
            System.out.println("I/O错误!");
        }
    }

}