l12.1b

来自「<B>Digital的Unix操作系统VAX 4.2源码</B>」· 1B 代码 · 共 61 行

#print
The function getnum actually returns -1 when it
encounters end of file. (The source is in getnum.c
if you're interested.)
Write, compile and run a program that
reads numbers one per line with getnum
and, for each, prints:

small	if the number is >0 and <=100
big	if the number is >100 and <=1000
huge	if the number is >1000.

Type "ready" when you're done.
#once cp %s/getnum.o .
#once cp %s/getnum.c .
#once #create Ref
1001
1000
999
101
100
1
#once #create Ref1
huge
big
big
big
small
small
#user
a.out <Ref >test
#cmp Ref1 test
#succeed
/* One way:*/

main() {
	int n;

	while ((n = getnum()) >= 0)
		if (n > 0 && n <= 100)
			printf("small\n");
		else if (n > 100 && n <= 1000)
			printf("big\n");
		else if (n > 1000)
			printf("huge\n");
}

/* 	Notice that in principle n could be negative,
	so we need the last case to say
		else if (n > 1000)
	instead of just falling into it with a bare
		else

	Also it's a good idea to indent the else-if's
	exactly the way they are here; otherwise
	you'll lose track of what's going on.
**/
#log
#next
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