c程序设计语言上的习题答案有些不懂，希望大家帮忙讲解下。
#include <stdio.h>
int main(void)
{
int blanks, tabs, newlines;
int c;
int done = 0;
int lastchar = 0;
blanks = 0;
tabs = 0;
newlines = 0;
while(done == 0)
{
c = getchar();
if(c == ' ')
++blanks;
if(c == '\t')
++tabs;
if(c == '\n')
++newlines;
if(c == EOF)
{
if(lastchar != '\n')
{
++newlines; /* this is a bit of a semantic stretch, but it copes
* with implementations where a text file might not
* end with a newline. Thanks to Jim Stad for pointing
* this out.
*/
}
done = 1;
}
lastchar = c;
}
printf("Blanks: %d\nTabs: %d\nLines: %d\n", blanks, tabs, newlines);
return 0;
}
你的写法更简洁 ，这样写就是为了下面的记录newlines变量的判断，当写完一行换行再输入文件结束标志时正确统计出写入的行数。
if(c == EOF)
{
if(lastchar != '\n')
{
++newlines; /* this is a bit of a semantic stretch, but it copes
* with implementations where a text file might not
* end with a newline. Thanks to Jim Stad for pointing
* this out.
*/
}
done = 1;
}
