c_ch01_ex11.c

/*
 * Exercise 1-11.
 * How would you test the word count program?
 * What kinds of input are most likely to uncover bugs if there are any?
 */

#include <stdio.h>
#define	IN   1  /* inside a word */
#define	OUT  0  /* outside a word */

/* count lines, words, and characters in input */

main() {
	int c, nl, nw, nc, state;
	state = OUT;
	nl = nw = nc = 0;


	while ((c = getchar()) != EOF) {
		++nc;
		if (c == '\n')
			++nl;
		if (c == ' ' || c == '\n' || c == '\t')
			state = OUT;
		else if (state == OUT) {
			state = IN;
			++nw;
		}
	}

	printf("%d %d %d\n", nl, nw, nc);
}