第三章例3-7

#include<stdio.h>
int main(void)
{
	int digit,letter,other;
	char ch;
	int i;
	digit=letter=other=0;
	printf("Enter 10 characters:");
	for(i=1;i<=10;i++){
		ch=getchar();
		if((ch>='a'&&ch<='z')||(ch>='A'&&ch<='Z'))
			letter++;
		else if(ch>='0'&&ch<='9')
			digit++;
		else
			other++;

	}
	printf("letter=%d,digit=%d,other=%d
",letter,digit,other);

	return 0;
}