程序代码：

#include "stdio.h"
#include <string.h>
#define p printf
int main(void)
{int l,n,s,o,sum,i;l=n=s=o=sum=0;

 char c[200];//说c未声明，，为什么啊？
 printf("Please input the string\n");

 gets(c);//报错，，
 for(i=0;i<strlen(c);i++)
  {sum++;
      if((c[i]>=48)&&(c[i]<=57))n++;
       else if(c[i]==32)s++;
            else if(((c[i]>=65)&&(c[i]<=90))||((c[i]>=97)&&(c[i]<=122)))l++;//这些if语句有问题吗？
                 else o++;
  }

 p("The summary is %d\n",sum);

 p("The number of letters is %d\n",l);

 p("The number of numbers is %d\n",n);

 p("The number of spacebars is %d\n",s);

 p("Other chars:%d\n",o);
}