1 files changed, 40 insertions, 2 deletions

diff --git a/main.c b/main.c
index ad07324..50a9f64 100644
--- a/main.c
+++ b/main.c
@@ -28,11 +28,49 @@ void max_clique_a(const graph g, set k, set c, set *mc) {
 			delete_set(k2);
 			delete_set(c2);
 		}
+		delete_set(cc);
 	}
 }
 
-int main() {
-	graph g = load_graph(stdin);
+
+// Driver
+
+void usage(char *pname) {
+	printf("\nUsage:\n\t%s [options] [<graph file>]\n\n", pname);
+	printf("Available options:\n");
+	printf("\n    -d\n\tRead input in DIMACS format\n");
+	printf("\n    -h, --help\n\tShow this help page\n");
+}
+
+int main(int argc, char **argv) {
+	int i;
+	int dimacs = 0;
+	char *filename = "-";
+
+	for (i = 1; i < argc; i++) {
+		if (!strcmp(argv[i], "-d")) {
+			dimacs = 1;
+		} else if (argv[i][0] == '-') {
+			usage(argv[0]);
+			return 0;
+		} else {
+			filename = argv[i];
+		}
+	}
+
+	FILE *f = stdin;
+	if (strcmp(filename, "-")) {
+		f = fopen(filename, "r");
+		if (f == NULL) {
+			fprintf(stderr, "Error: could not open file %s\n", filename);
+			return 1;
+		}
+	}
+	graph g = (dimacs ? load_graph_dimacs(f) : load_graph(f));
+	if (g == NULL) {
+		fprintf(stderr, "Error loading file %s\n", filename);
+		return 1;
+	}
 	dump_graphviz(g, stdout);
 
 	// do stuff with graph