課本4-1練習－老人家的舊書房

Jan 23 Tue 2007 01:49
課本4-1練習

請撰寫程式，宣告一個變數i，如果i的值小於31，就顯示2的i次方的值。

import java.io.*;

public class ex4_1{
public static void main(String[] argv)
throws IOException{
BufferedReader b = new BufferedReader(new InputStreamReader(System.in));
System.out.println("→");
String i = b.readLine();
int y = Integer.parseInt(i);
if(y <=30){
long j = 1;
for(int x = 0;xj = j * 2;
}
System.out.println(j);
}
else {
System.out.println("超出數值，請重新輸入");
}
}
}