C语言输入一个字符

void main()
{
int i;
int num = 0, cha = 0, spa = 0, oth = 0;
char s[80];
printf("please input a sentence:\n");
gets(s);
for(i = 0; i < 80; i++)
{
if(s[i] == ' ')
{
spa++;
}
else if(s[i] >= '0' && s[i] <= '9')
{
num++;
}
else if((s[i] >= 'a' && s[i] <= 'z') || (s[i] >= 'A' && s[i] <= 'Z '))
{
cha++;
}
else
{
oth++;
}
}
printf("char:%d\nnumber:%d\nspace:%d\nother:%d\n", cha, num, spa, oth);
getch();

}