day 1 finished

day1/c/Makefile

@@ -0,0 +1,9 @@
+CC=gcc
+CFLAGS=-std=gnu99 -O2 -g
+PROJECT=aoc_day1
+
+%.o: %.c
+	$(CC) -c -o $@ $< $(CFLAGS)
+
+$(PROJECT): aoc_day1.o
+	$(CC) -o aoc_day1 aoc_day1.o

day1/c/aoc_day1.c

@@ -0,0 +1,64 @@
+#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;
+}