#include<stdio.h>
int main()
{void count(char *p,int i);
int letters=0,digit=0,other=0,i=0;
char *p,s[20];
printf("input string: ");
while((s[i]=getchar())!='\n')i++;
p=&s[0];
count(p,i);
printf("letters:%d\ndigit:%d\nother:%d\n",letters,digit,other);
printf("\n");
return 0;}

void count(char *p,int i)
{int letters=0,digit=0,other=0;
while(*p!='\n') p++;
{if((*p>='A' && *p<='Z')||(*p>='a' && *p<='z'))
    letters++;
else if(*p>='0' && *p<='9')
digit++;
else
other++;}
}

[ 本帖最后由 Bailey_27 于 2012-5-31 14:21 编辑 ]

有点乱

我又改了一下 你看下吧  没有错误 但是不知道为什么数据统计不出来
#include<stdio.h>
int main()
{void count(char *p,int i);
int letters=0,digit=0,other=0,i=0;
char *p,s[20];
printf("input string: ");
while((s[i]=getchar())!='\n')i++;
p=&s[0];
count(p,i);
printf("letters:%d\ndigit:%d\nother:%d\n",letters,digit,other);
printf("\n");
return 0;}

void count(char *p,int i)
{int letters=0,digit=0,other=0;
while(*p!='\n') p++;
{if((*p>='A' && *p<='Z')||(*p>='a' && *p<='z'))
    letters++;
else if(*p>='0' && *p<='9')
digit++;
else
other++;}
}

#include<stdio.h>

void count(char *p,int i,int *, int *, int *);

int main()
{
    int letters=0,digit=0,other=0,i=0;
    char *p,s[20];
    printf("input string: ");
    while((s[i]=getchar())!='\n')i++;
    p=&s[0];
    count(p,i, &letters, &digit, &other);
    printf("letters:%d\ndigit:%d\nother:%d\n",letters,digit,other);
    printf("\n");
    return 0;
}

void count(char *p,int i, int *letters, int *digit, int *other)
{
    while(*p!='\n')
    {
        if((*p>='A' && *p<='Z') || (*p>='a' && *p<='z'))
            (*letters)++;
        else if(*p>='0' && *p<='9')
            (*digit)++;
        else
            (*other)++;
        p++;
    }
}

恩恩  谢谢