Ben, blogging: A programming problem.

Friday, January 7

A program:

     ...

again:n=a();

   if (n>0) {

      n=b;

      goto again;

   }

...

You know, goto is not a good style in programming. How to get rid of "goto" in this code?

try:

// wrong program.

do{

 n=a();

}while(n>0);

Where is "n=b"?

Need Help!

Damon gave a neat solution:

n=a();
while(n>0){
n=b;
n=a();
}

It's very beautiful.

Now my question changed to:

     ...

again:n=a();

     if (n>0) {

      n=b;

      goto again;

     }

     else{

        n=c();

     }

    ...

???

At January 09, 2005 1:19 AM, Anonymous said...: again:n=a();
if (n>0) {
n=b;
goto again;
}
else{
n=c();
}

我不太看得懂这段程序是什么意思，就我看来，直接改成这样：

n=c();

因为当a()返回值总大于0时，这是一个死循环。只有在a()返回值小于等于0时，n=c()。

其实前面的程序就有问题：

n=a();
while(n>0){
n=b;
n=a();
}

这一段程序执行完毕之后，n无论如何不可能为b，看不出有何意义。
At January 10, 2005 10:16 AM, Unknown said...: Actually, "n=a()", "n=b", "n=c()" only mean "Command 1", "Command 2", "Command 3" in the post. I'm thinking of the 流程 of the program, not the detail command.

The last code can be changed as:

n=a();
while(n>0){
n=b;
n=a();
}
n=c();
----------------------
As I said, it means:
...
Command 1;
while (n>0){
Command 2;
Command 1;
}
Command 3;
...