check for minimum of 2 points

src/read_file.c

@@ -250,7 +250,7 @@ int read_file(char *filename, point_t **points, unsigned int *n) {
 		buffer = NULL;
 		size = 0;
 	}
-	if (j < *n) {
+	if (j < *n || *n < 2) {
 		fprintf(stderr, "Error: No hay suficiente puntos!\n");
 		return 9;
 	}