统计行数、单词数，字符数的程序： 

1 #include
     
       2  3 #define IN    1   /*在单词内*/ 4 #define OUT   0   /*在单词外*/ 5  6 int main() 7 { 8     int c, nl, nw, nc, state; 9 10     state = OUT;11     nl = nw = nc  = 0;    //nl：行数  nw：单词数  nc：字符数12     while((c = getchar()) != EOF) {13         ++nc;14         if(c == '\n')15             ++nl;16         if(c == ' ' || c == '\n' || c == '\t')17             state = OUT;18         else if (state == OUT) {19             state = IN;20             ++nw;21         }22     }23     printf("%d %d %d\n", nl, nw, nc);24     return 0;25 }
     

【练习1-12】 
编写一个程序，以每行一个单词的形式打印其输入 

1 #include
     
       2  3 #define IN    1   /*在单词内*/ 4 #define OUT   0   /*在单词外*/ 5  6 int main() 7 { 8     int c, state; 9     state = OUT;10     11     while((c =getchar()) != EOF) {12         if(c == ' ' || c == '\n' || c == '\t') {13             if(state == IN) {14                 putchar('\n');15                 state = OUT;16             }17         } else if(state == OUT) {18             state = IN;19             putchar(c);20         } else {21             putchar(c);22         }23     }24     return 0;25 }