Initial commit

4 files changed, 44 insertions, 0 deletions

diff --git a/2015/04/.gitignore b/2015/04/.gitignore
new file mode 100644
index 0000000..60d075d
--- /dev/null
+++ b/2015/04/.gitignore
@@ -0,0 +1 @@
+puzzle-[12]
diff --git a/2015/04/Makefile b/2015/04/Makefile
new file mode 100644
index 0000000..10ec8f9
--- /dev/null
+++ b/2015/04/Makefile
@@ -0,0 +1,7 @@
+all:
+	${CC} ${CFLAGS} -lmd -DINPUT=\"$$(cat input)\" -o puzzle-1 puzzles.c
+	${CC} ${CFLAGS} -lmd -DINPUT=\"$$(cat input)\" -DPART2 -o puzzle-2 puzzles.c
+
+.PHONY: clean
+clean:
+	rm -f puzzle-[12]
diff --git a/2015/04/input b/2015/04/input
new file mode 100644
index 0000000..bf3e46f
--- /dev/null
+++ b/2015/04/input
@@ -0,0 +1 @@
+bgvyzdsv
diff --git a/2015/04/puzzles.c b/2015/04/puzzles.c
new file mode 100644
index 0000000..22833a2
--- /dev/null
+++ b/2015/04/puzzles.c
@@ -0,0 +1,35 @@
+#include <sys/types.h>
+
+#include <md5.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define BUFFER 128
+#ifdef PART2
+	#define ZEROS     "000000"
+	#define NUM_ZEROS 6
+#else
+	#define ZEROS     "00000"
+	#define NUM_ZEROS 5
+#endif
+
+int
+main(void)
+{
+	unsigned int i = 0;
+	char buffer[MD5_DIGEST_STRING_LENGTH], digest[BUFFER];
+	MD5_CTX ctx;
+
+	do {
+		snprintf(digest, BUFFER, INPUT "%u", i);
+
+		MD5Init(&ctx);
+		MD5Update(&ctx, (uint8_t *) digest, strlen(digest));
+		MD5End(&ctx, buffer);
+	} while (strncmp(buffer, ZEROS, NUM_ZEROS) && ++i);
+
+	printf("%u\n", i);
+	return EXIT_SUCCESS;
+}