Day01

2025/gareth/day01/day01.go

@@ -0,0 +1,64 @@
+package day01
+
+import (
+	"strconv"
+	"strings"
+)
+
+func Part1(input string) int {
+	lines := strings.Split(input, "\n")
+
+	position := 50
+	output := 0
+
+	for _, line := range lines {
+		direction := line[0]
+		amount, _ := strconv.Atoi(line[1:])
+
+		if direction == 'R' {
+			position += amount
+			for position > 99 {
+				position -= 100
+			}
+		} else if direction == 'L' {
+			position -= amount
+			for position < 0 {
+				position += 100
+			}
+		}
+
+		if position == 0 {
+			output++
+		}
+	}
+
+	return output
+}
+
+func Part2(input string) int {
+	lines := strings.Split(input, "\n")
+	position := 50
+	output := 0
+
+	for _, line := range lines {
+		direction := line[0]
+		amount, _ := strconv.Atoi(line[1:])
+
+		step := 1
+		if direction == 'L' {
+			step = -1
+		}
+
+		for i := 0; i < amount; i++ {
+			position = (position + step) % 100
+			if position < 0 {
+				position += 100
+			}
+			if position == 0 {
+				output++
+			}
+		}
+	}
+
+	return output
+}

2025/gareth/day01/day01_test.go

@@ -0,0 +1,35 @@
+package day01
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestPart1(t *testing.T) {
+	r := Part1(`L68
+L30
+R48
+L5
+R60
+L55
+L1
+L99
+R14
+L82`)
+	assert.Equal(t, 3, r)
+}
+
+func TestPart2(t *testing.T) {
+	r := Part2(`L68
+L30
+R48
+L5
+R60
+L55
+L1
+L99
+R14
+L82`)
+	assert.Equal(t, 6, r)
+}

2025/gareth/day01/poc.py

@@ -0,0 +1,49 @@
+def part1(input_file):
+    file = open(input_file, "r")
+    line = file.readline()
+
+    position = 50
+    output = 0
+    while line:
+        direction = line[0]
+        amount = int(line[1:])
+
+        if direction == "R":
+            position += amount
+            while position > 99:
+                position -= 100
+
+        elif direction == "L":
+            position -= amount
+            while position < 0:
+                position += 100
+
+        if position == 0:
+            output += 1
+
+        line = file.readline()
+
+    file.close()
+    print("Part 1:", output)
+
+def part2(input_file):
+    position = 50
+    output = 0
+
+    with open(input_file) as file:
+        for line in file:
+            line = line.strip()
+            direction = line[0]
+            amount = int(line[1:])
+
+            step = 1 if direction == "R" else -1
+
+            for _ in range(amount):
+                position = (position + step) % 100
+                if position == 0:
+                    output += 1
+
+    print("Part 2:", output)
+
+part1("input.txt")
+part2("input.txt")