AdventOfCode/2015/c/Day_1/main.c

#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>

#define IMP
#include "../file.h"

size_t cstr_char_count(const char *cstr, char c);
int cmp_sort(const void *this, const void *other);

int
main(int argc, char *argv[])
{
	enum file_err ferr;
	long res = 0;

	char *raw_input = NULL;
	size_t raw_input_size = 0;
	raw_input = (char *) file_read_all("./input.txt", 
					   &raw_input_size,
					   &ferr);
	if ( ferr != FILE_ERR_OK ) {
		fprintf(stderr, "Failed to open file: %s\n", 
			file_err_to_cstr(ferr));
		exit(EXIT_FAILURE);
	}

	if ( argc == 1 ) {
		char *cstr = raw_input;

loop_p1:
		switch ( *(cstr++) ) {
		case '\0':
			goto exit_loop;
		case '(':
			++res;
			break;
		case ')':
			--res;
			break;
		}
		goto loop_p1;
	} else {
		size_t i = 0;
		char *cstr = raw_input;

loop_p2:
		switch ( *(cstr + i) ) {
		case '\0':
			goto exit_loop;
		case '(':
			++res;
			break;
		case ')':
			--res;
			if ( res < 0 ) {
				res = ((long) i) + 1;
				goto exit_loop;
			}
			break;
		}
		++i;
		goto loop_p2;
	}

exit_loop:
	printf("Result: %ld\n", res);

	free(raw_input);

	(void) argc; (void) argv;
	return 0;
}

size_t 
cstr_char_count(const char *cstr, char c)
{
	size_t ret = 0;
	while ( *cstr != '\0' ) {
		ret += ( *cstr == c );
		cstr++;
	}
	return ret;
}

int 
cmp_sort(const void *this, const void *other)
{
	long this_ = *((long*) this);
	long other_ = *((long*) other);

	return (int) (this_ - other_);
}