3 files changed, 36 insertions, 59 deletions

diff --git a/4a.c b/4.c
index 76d5e0c..1f183b7 100644
--- a/4a.c
+++ b/4.c
@@ -1,6 +1,7 @@
 
 #include <stdio.h>
 #include <stdlib.h>
+#include <unistd.h>
 
 
 char *
@@ -22,10 +23,21 @@ getsect(int * dest, char * pch, char expect)
 
 
 int
-main()
+main(int argc, char ** argv)
 {
 	char buf[BUFSIZ];
-	int overlaps = 0;
+	int part = 1, i, overlaps = 0;
+
+	while ((i = getopt(argc, argv, "p:")) != -1) {
+		switch (i) {
+		case 'p':
+			part = atoi(optarg);
+			break;
+
+		default:
+			return -1;
+		}
+	}
 
 	while (fgets(buf, sizeof(buf), stdin)) {
 		int n[4];
@@ -39,14 +51,30 @@ main()
 			fprintf(stderr, "Unexpected line: %s\n", buf);
 			return -1;
 		}
-		if ((n[2] >= n[0] && n[3] <= n[1])
-				|| (n[0] >= n[2] && n[1] <= n[3]))
-		{
-			++overlaps;
+		switch (part) {
+		case 1:
+			if ((n[2] >= n[0] && n[3] <= n[1])
+					|| (n[0] >= n[2] && n[1] <= n[3]))
+			{
+				++overlaps;
+			}
+			break;
+
+		case 2:
+			if (!(n[3] < n[0] || n[2] > n[1])) {
+				++overlaps;
+			}
+			break;
+
+		default:
+			fprintf(stderr, "Unexpected puzzle part %d\n", part);
+			return -1;
 		}
 	}
 
-	printf("Overlaps: %d\n", overlaps);
+	printf("%s overlaps: %d\n",
+			part == 1 ? "Full" : "Partial",
+			overlaps);
 
 	return 0;
 }
diff --git a/4b.c b/4b.c
deleted file mode 100644
index 6f43c21..0000000
--- a/4b.c
+++ /dev/null
@@ -1,51 +0,0 @@
-
-#include <stdio.h>
-#include <stdlib.h>
-
-
-char *
-getsect(int * dest, char * pch, char expect)
-{
-	char * end;
-
-	if (!pch)
-		return NULL;
-	*dest = strtol(pch, &end, 10);
-	if (*dest == 0 && end == pch)
-		return NULL;
-	if (*end != expect)
-		return NULL;
-	if (expect)
-		++end;
-	return end;
-}
-
-
-int
-main()
-{
-	char buf[BUFSIZ];
-	int overlaps = 0;
-
-	while (fgets(buf, sizeof(buf), stdin)) {
-		int n[4];
-		char * pbuf;
-
-		pbuf = getsect(&n[0], buf, '-');
-		pbuf = getsect(&n[1], pbuf, ',');
-		pbuf = getsect(&n[2], pbuf, '-');
-		pbuf = getsect(&n[3], pbuf, '\n');
-		if (!pbuf) {
-			fprintf(stderr, "Unexpected line: %s\n", buf);
-			return -1;
-		}
-		if (!(n[3] < n[0] || n[2] > n[1])) {
-			++overlaps;
-		}
-	}
-
-	printf("Overlaps: %d\n", overlaps);
-
-	return 0;
-}
-
diff --git a/makefile b/makefile
index ad777c2..21ddbb3 100644
--- a/makefile
+++ b/makefile
@@ -5,7 +5,7 @@ all: bin \
 	bin/1 \
 	bin/2 \
 	bin/3 \
-	bin/4a bin/4b \
+	bin/4 \
 	bin/5 \
 	bin/6 \
 	bin/7 \