c语言统计英文大小写字母，空格，数字，以及其他字符的个数并以#结束

#include <stdio.h>
int main(int argc, const char * argv[]) {
    char c;
    int letters=0,space=0,digit=0,others=0;
    while((c=getchar())!='#')
    {
        if ((c>='a'&&c<='z')||(c>='A'&&c<='Z')) {
            letters++;
        }
        else if(c==' ')
        {
            space++;
        }
        else if (c>='0'&&c<='9')
        {
            digit++;
        }
        else
        {
            others++;
        }
    }
    printf("letters=%d,space=%d,digit=%d,others=%d\n",letters,space,digit,others);
    return 0;
}

output:

123456qwerty \\\\
#
letters=6,space=1,digit=6,others=5
Program ended with exit code: 0