ex1.6.c

#include <stdio.h>

/* count digits, white space, others */
int main()
{
	int c, i, nwhite = 0, nother = 0;
	int ndigit[10];
	for(i=0; i < 10; i++)
		ndigit[i]=0;

	while((c = getchar()) != EOF)
		if (c >= '0' && c <= '9')
			++ndigit[c - '0'];
		else if(c == ' ' || c == '\n' || c == '\t')
			++nwhite;
		else
			++nother;

	printf("digits =");
	for(i=0;i < 10;++i)
		printf(" %d", ndigit[i]);
	printf(", white space = %d, other = %d\n", nwhite, nother);
}