Question

public class BeerSong {
    public static void main(String[] args) {
        int beerNum = 99;
        String word = "bottles";
        while (beerNum > 0) {
            System.out.println(beerNum + " " + word + " of beer on the wall");
            System.out.println(beerNum + " " + word + " of beer.");
            System.out.println("Take one down.");
            System.out.println("Pass it around.");
            beerNum = beerNum - 1;
            if (beerNum == 1) {
                word = "bottle";  // singular, as in ONE bottle.
            }
            if (beerNum > 0) {
                System.out.println(beerNum + " " + word + " of beer on the wall");
            } else {
                System.out.println("No more bottles of beer on the wall");
            }  // end else
        } // end while loop
    }  // end main method
}  // end class

此代码打印出来：

99 bottles of beer on the wall
99 bottles of beer on the wall.
99 bottles of beer.
Take one down and pass it around.

为什么不这样打印：

99 bottles of beer on the wall
99 bottles of beer. 
Take one down and pass it around, 99 bottles of beer on the wall.

因为if语句在循环之后

Answer 1

这种情况正在破坏代码：

if (beerNum > 0) {
        System.out.println(beerNum + " " + word + " of beer on the     wall");
} else {
        System.out.println("No more bottles of beer on the wall");
} // end else

如果数字不为零，你正在检查瓶子并打印......

你应该用以下内容替换那个逻辑：

if (beerNum == 0) {
    System.out.println(beerNum + " " + word + " of beer on the wall");
}

之后，这首歌会很好地播放：）

最终代码可能如下：

public static void main(String[] args) {
int beerNum = 99;
String word = "bottles";
while (beerNum > 0) {
    System.out.println(beerNum + " " + word + " of beer on the wall");
    System.out.println(beerNum + " " + word + " of beer.");
    System.out.println("Take one down.");
    System.out.println("Pass it around.");
    beerNum = beerNum - 1;
    if (beerNum == 1) {
    word = "bottle"; // singular, as in ONE bottle.
    } else if (beerNum == 0) {
    word = "bottles";
    System.out.println(beerNum + " " + word + " of beer on the wall");
    }
} 
}

如果在一个while循环内

1 个答案: