1 files changed, 60 insertions, 0 deletions
diff --git a/6.3/tree.c b/6.3/tree.c
new file mode 100644
index 0000000..c58da53
--- /dev/null
+++ b/6.3/tree.c
@@ -0,0 +1,60 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <error.h>
+#include <errno.h>
+#include "tree.h"
+
+struct tnode *talloc(void);
+
+struct tnode *addtree(struct tnode *p, char *w, int line)
+{
+	int cond;
+
+	if (p == NULL) {
+		p = talloc();
+		p->word = strdup(w);
+		p->lc = 0;
+		p->lines[p->lc++] = line;
+		p->left = p->right = NULL;
+	} else if (!(cond = strcasecmp(w, p->word))) {
+		if (p->lc < MAXLINES)
+			p->lines[p->lc++] = line;
+		else
+		 	error(EXIT_FAILURE, ENOBUFS, "addtree");
+	} else if (cond < 0) {
+		p->left = addtree(p->left, w, line);
+	} else if (cond > 0) {
+		p->right = addtree(p->right, w, line);
+	}
+
+	return p;
+}
+
+void tprint(struct tnode *p)
+{
+	int lc;
+
+	if (p != NULL) {
+		tprint(p->left);
+		printf("---> %s\n", p->word);
+		for (lc = 0; lc < p->lc; ++lc)
+			printf((lc == p->lc-1) ? "%d" : "%d, ", p->lines[lc]);
+		putchar('\n');
+		tprint(p->right);
+	}
+}
+void tfree(struct tnode *p)
+{
+	if (p != NULL) {
+		tfree(p->left);
+		tfree(p->right);
+		free(p->word);
+		free(p);
+	}
+}
+
+struct tnode *talloc(void)
+{
+	return (struct tnode *) malloc(sizeof(struct tnode));
+}