don't segfault if no file is found geez

4/4.c

@@ -19,6 +19,7 @@ SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
 int main(int argc, char* args[]) {
   FILE* file = fopen("input", "r");
+  if (!file) return 0;
   size_t length = get_filesize(file);
   char* input = calloc(length, sizeof(char));
   fread(input, sizeof(char), length, file);

4/4a.c

@@ -20,6 +20,7 @@ SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
 int main(int argc, char* args[]) {
   FILE* file = fopen("input", "r");
+  if (!file) return 0;
   size_t length = get_filesize(file);
   char* input = calloc(length, sizeof(char));
   fread(input, sizeof(char), length, file);

5/5.c

@@ -18,6 +18,7 @@ SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
 int main(int argc, char* args[]) {
   FILE* file = fopen("input", "r");
+  if (!file) return 0;
   size_t length = get_filesize(file);
   char* input = calloc(length, sizeof(char));
   fread(input, sizeof(char), length, file);

6/6a.c

@@ -21,6 +21,7 @@ SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
 int main(int argc, char* args[]) {
   FILE* file = fopen("input", "r");
+  if (!file) return 0;
   size_t length = get_filesize(file);
   char* input = calloc(length, sizeof(char));
   fread(input, sizeof(char), length, file);

6/6b.c

@@ -20,6 +20,7 @@ SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
 int main(int argc, char* args[]) {
   FILE* file = fopen("input", "r");
+  if (!file) return 0;
   size_t length = get_filesize(file);
   char* input = calloc(length, sizeof(char));
   fread(input, sizeof(char), length, file);

7/7.c

@@ -82,6 +82,7 @@ int part1() {
 
 int main(int argc, char* args[]) {
   FILE* file = fopen("input", "r");
+  if (!file) return 0;
   size_t length = get_filesize(file);
   char* input = calloc(length, sizeof(char));
   fread(input, sizeof(char), length, file);

8/8a.c

@@ -52,6 +52,7 @@ void execute() {
 
 int main(int argc, char* args[]) {
   FILE* file = fopen("input", "r");
+  if (!file) return 0;
   instructions = calloc(1, sizeof(char*));
   // each line is max 8 char + null terminator
   instructions[0] = calloc(9, sizeof(char));

8/8b.c

@@ -85,6 +85,7 @@ int part2(char** program, int line_amount) {
 
 int main(int argc, char* args[]) {
   FILE* file = fopen("input", "r");
+  if (!file) return 0;
   char** instructions = 0;
   int32_t acc = 0;
   int i_amount = 0;

README.md

@@ -0,0 +1,15 @@
+# Advent of Code 2020
+
+#### by Aoife Bradley
+
+---
+
+If you want to test it with your input, place it with your input in a file called "input" beside the executable of the day.
+
+only tested on ubuntu 20.10
+
+compiled with `gcc -g x.c -o ./x -msse4.2`
+
+I tried to make each day with no leaks or memory issues.
+
+lemme know if there are any issues with the code. :)