csample2.c

c51学习的好书！

 #include <stdio.h>                    
 getline (char *line) {
   while ((*line++ = getchar()) != '\n');
 }
 int atoi (char *line) {
   bit sign;
   int number;
  /* 忽略空白字符 */
   for ( ; *line == ' ' || *line == '\n' || *line == '\t'; line++);
  /* 设置符号 */
   sign = 1;
   if (*line == '+' || *line == '-')  sign = (*line++ == '+');
  /* 计算并返回十进制整数 */
   for (number=0; *line >= '0' && *line <= '9'; line++)
      number = (number * 10) + (*line - '0');
   return (sign ? number : -number);
 }
  /* 输入并返回一个十进制整数 */
 unsigned int getnumber () {
   char line [40];
   printf ("Input Number ? ");
   getline (line);
   return (atoi (line));
 }