#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdint.h>

#define INPUT_FILE ("input.txt")
#define ARR_LEN (2000)

int main(int argc, char** argv)
{
	int measurements[ARR_LEN];
	memset(measurements, 0, ARR_LEN * sizeof(int));
	FILE* fp = fopen(INPUT_FILE, "r");
	if(fp == NULL)
	{
		printf("File failed to open for reading...");
		exit(-1);
	}

	char* line = NULL;
	size_t len = 0;
	ssize_t rc = 0;
	uint16_t ct = 0;

	// counter that keeps track of how many times a depth measurement has increased
	int increase_count = 0;

	if((rc = getline(&line, &len, fp)) < 0)
	{
		printf("Bad read...\n");
		exit(-1);
	}
	else
	{
		measurements[ct++] = strtol(line, NULL, 10);
	}

	while((rc = getline(&line, &len, fp)) >= 0)
	{
		measurements[ct] = strtol(line, NULL, 10);
		if(measurements[ct] - measurements[ct - 1] > 0)
		{
			increase_count++;
		}
		ct++;
	}
	printf("Increase count: %d\n", increase_count);

	// part 2
	int sum_increase_count = 0;
	for(int ind = 2; ind < ARR_LEN - 1; ind++)
	{
		int sum_one = measurements[ind - 2] +
			measurements[ind - 1] +
			measurements[ind];
		int sum_two = measurements[ind - 1] +
			measurements[ind] +
			measurements[ind + 1];
		sum_increase_count += (sum_two > sum_one);
	}
	printf("Sum increase count: %d\n", sum_increase_count);

	return 0;
}