程序功能:从键盘输入一个字符串输出这个字符串中的英文字母,数字,空格,其他的个数
#include<stdio.h>
void main(void)
{
     int letter=0,num=0,space=0,other=0;
     char *input;
     printf("input string\n");
      scanf("%s",input);
     while(*(input++)!='\n')
     {
         if(*input==' ')
             space++;
         else if(*input>=0&&*input<=9)
             num++;
         else if((*input>='a'&&*input<='z')||(*input>='A'&&*input<='Z'))
             letter++;
         else other++;
     }
     printf("letter=%d\nnum=%d\nspace=%d\nother=%d\n",letter,num,space,other);
}

嗯,谢谢了,感激不尽!!!!!