Day14

2024/gareth/day14/day14.go

@@ -0,0 +1,172 @@
+package day14
+
+import (
+	"fmt"
+	"strconv"
+	"strings"
+)
+
+type Robot struct {
+	px, py int // position
+	vx, vy int // velocity
+}
+
+func Part1(input string) int {
+	// Parse the input
+	lines := strings.Split(input, "\n")
+	var robots []Robot
+	for _, line := range lines {
+		robot := ParseRobot(line)
+		robots = append(robots, robot)
+	}
+
+	// Define grid size
+	gridWidth := 101
+	gridHeight := 103
+
+	// Update robot positions for 100 seconds
+	for i := 0; i < 100; i++ {
+		for j := range robots {
+			robots[j].UpdatePosition(gridWidth, gridHeight)
+		}
+	}
+
+	// Count the robots in each quadrant
+	q1, q2, q3, q4 := CountRobotsInQuadrants(robots, gridWidth, gridHeight)
+	fmt.Printf("Quadrant counts: Q1=%d, Q2=%d, Q3=%d, Q4=%d\n", q1, q2, q3, q4)
+
+	// Calculate the safety factor
+	safetyFactor := CalculateSafetyFactor(q1, q2, q3, q4)
+	fmt.Printf("Safety Factor: %d\n", safetyFactor)
+	return safetyFactor
+}
+
+func Part2(input string) int {
+	// Parse the input
+	lines := strings.Split(input, "\n")
+	var robots []Robot
+	for _, line := range lines {
+		robot := ParseRobot(line)
+		robots = append(robots, robot)
+	}
+
+	// Define grid size
+	gridWidth := 101
+	gridHeight := 103
+
+	// Update robot positions for 100 seconds
+	for i := 0; i < 6285; i++ {
+		for j := range robots {
+			robots[j].UpdatePosition(gridWidth, gridHeight)
+		}
+	}
+
+	DisplayGrid(robots, gridWidth, gridHeight)
+	return 2
+}
+
+// ParseRobot takes a line of input and converts it to a Robot struct
+func ParseRobot(line string) Robot {
+	parts := strings.Split(line, " ")
+	posParts := strings.Split(parts[0][2:], ",") // Extract p=x,y and split
+	velParts := strings.Split(parts[1][2:], ",") // Extract v=x,y and split
+
+	px, _ := strconv.Atoi(posParts[0])
+	py, _ := strconv.Atoi(posParts[1])
+	vx, _ := strconv.Atoi(velParts[0])
+	vy, _ := strconv.Atoi(velParts[1])
+
+	return Robot{px, py, vx, vy}
+}
+
+// UpdatePosition updates the position of a robot, considering the wrap-around
+func (r *Robot) UpdatePosition(gridWidth, gridHeight int) {
+	r.px = (r.px + r.vx + gridWidth) % gridWidth
+	r.py = (r.py + r.vy + gridHeight) % gridHeight
+}
+
+// CountRobotsInQuadrants counts the number of robots in each of the four quadrants
+func CountRobotsInQuadrants(robots []Robot, width, height int) (int, int, int, int) {
+	midX := width / 2
+	midY := height / 2
+
+	q1, q2, q3, q4 := 0, 0, 0, 0
+
+	for _, r := range robots {
+		if r.px == midX || r.py == midY {
+			// Skip robots on the middle line
+			continue
+		}
+		if r.px < midX && r.py < midY {
+			q1++ // Top-left quadrant
+		} else if r.px > midX && r.py < midY {
+			q2++ // Top-right quadrant
+		} else if r.px < midX && r.py > midY {
+			q3++ // Bottom-left quadrant
+		} else if r.px > midX && r.py > midY {
+			q4++ // Bottom-right quadrant
+		}
+	}
+
+	return q1, q2, q3, q4
+}
+
+// CalculateSafetyFactor multiplies the number of robots in each quadrant
+func CalculateSafetyFactor(q1, q2, q3, q4 int) int {
+	return q1 * q2 * q3 * q4
+}
+
+// DisplayGrid displays the current state of the grid
+func DisplayGrid(robots []Robot, width, height int) {
+	grid := make([][]rune, height)
+	for i := range grid {
+		grid[i] = make([]rune, width)
+		for j := range grid[i] {
+			grid[i][j] = '.'
+		}
+	}
+	for _, r := range robots {
+		grid[r.py][r.px] = '#'
+	}
+	for _, row := range grid {
+		fmt.Println(string(row))
+	}
+}
+
+// FindEasterEgg determines the fewest number of seconds that must elapse for the robots to display the Easter egg
+func FindEasterEgg(robots []Robot, width, height int) int {
+	smallestArea := width * height
+	bestTime := 0
+	for t := 6285; t < 6286; t++ { // Large upper limit to search
+		// Update robot positions
+		for i := range robots {
+			robots[i].UpdatePosition(width, height)
+		}
+		// Calculate the bounding box of all robot positions
+		minX, minY := width, height
+		maxX, maxY := 0, 0
+		for _, r := range robots {
+			if r.px < minX {
+				minX = r.px
+			}
+			if r.px > maxX {
+				maxX = r.px
+			}
+			if r.py < minY {
+				minY = r.py
+			}
+			if r.py > maxY {
+				maxY = r.py
+			}
+		}
+
+		area := (maxX - minX + 1) * (maxY - minY + 1)
+		if area < smallestArea {
+			smallestArea = area
+			bestTime = t + 1
+			fmt.Printf("Time: %d\n", bestTime)
+			DisplayGrid(robots, width, height)
+		}
+	}
+	return bestTime
+}

2024/gareth/day14/day14_test.go

@@ -0,0 +1,23 @@
+package day14
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestPart1(t *testing.T) {
+	r := Part1(`p=0,4 v=3,-3
+p=6,3 v=-1,-3
+p=10,3 v=-1,2
+p=2,0 v=2,-1
+p=0,0 v=1,3
+p=3,0 v=-2,-2
+p=7,6 v=-1,-3
+p=3,0 v=-1,-2
+p=9,3 v=2,3
+p=7,3 v=-1,2
+p=2,4 v=2,-3
+p=9,5 v=-3,-3`)
+	assert.Equal(t, 12, r)
+}

2024/gareth/day14/input.txt

@@ -0,0 +1,500 @@
+p=38,76 v=-61,88
+p=28,22 v=-43,-40
+p=76,78 v=-98,87
+p=39,56 v=10,96
+p=38,0 v=79,-15
+p=6,44 v=-88,53
+p=40,80 v=-83,31
+p=11,2 v=28,-31
+p=41,91 v=-86,-48
+p=8,55 v=-81,95
+p=77,19 v=3,-90
+p=94,73 v=-59,42
+p=51,53 v=35,48
+p=12,52 v=72,6
+p=62,61 v=96,47
+p=78,62 v=47,-57
+p=39,54 v=53,50
+p=1,43 v=-64,-46
+p=9,21 v=28,-36
+p=92,79 v=67,-47
+p=6,15 v=-58,-48
+p=54,67 v=99,-38
+p=96,99 v=-55,30
+p=90,44 v=-10,-8
+p=23,84 v=20,77
+p=5,84 v=28,88
+p=55,20 v=-31,-36
+p=84,43 v=-37,-41
+p=12,75 v=-38,30
+p=39,2 v=-12,-29
+p=74,14 v=56,-81
+p=63,53 v=22,-53
+p=51,28 v=9,-90
+p=53,72 v=48,-61
+p=33,42 v=-43,23
+p=75,18 v=-89,-37
+p=38,83 v=27,38
+p=69,31 v=61,80
+p=73,3 v=-45,74
+p=39,29 v=92,17
+p=78,45 v=-23,-47
+p=48,59 v=-57,38
+p=2,41 v=-71,-93
+p=30,13 v=36,-82
+p=37,57 v=25,13
+p=51,73 v=56,-98
+p=76,78 v=38,91
+p=56,49 v=22,55
+p=34,47 v=10,84
+p=83,93 v=81,-16
+p=14,70 v=71,-50
+p=97,74 v=-4,70
+p=33,8 v=93,-35
+p=39,70 v=-2,19
+p=94,63 v=20,44
+p=86,4 v=-33,19
+p=17,67 v=26,44
+p=39,2 v=-70,-25
+p=47,56 v=-79,-55
+p=5,98 v=86,-75
+p=53,21 v=79,-89
+p=53,85 v=61,73
+p=46,32 v=66,54
+p=30,75 v=49,-73
+p=44,81 v=-61,-69
+p=82,66 v=-72,-6
+p=89,76 v=-13,98
+p=57,87 v=30,36
+p=12,41 v=59,-40
+p=36,56 v=10,-61
+p=60,80 v=48,39
+p=50,75 v=-44,42
+p=66,56 v=-93,-1
+p=57,96 v=83,-79
+p=98,88 v=-15,-16
+p=0,63 v=59,44
+p=90,27 v=29,-40
+p=21,60 v=-86,2
+p=85,13 v=11,61
+p=92,77 v=24,-34
+p=16,24 v=80,4
+p=47,8 v=-79,-49
+p=1,28 v=-82,-48
+p=80,55 v=6,-72
+p=60,94 v=-67,-15
+p=83,90 v=-98,78
+p=3,75 v=46,-66
+p=93,40 v=15,11
+p=52,37 v=48,7
+p=23,4 v=-47,25
+p=46,43 v=57,-98
+p=23,12 v=-98,-36
+p=11,42 v=-83,50
+p=80,33 v=25,54
+p=59,95 v=-1,36
+p=55,67 v=-44,-60
+p=90,80 v=83,-39
+p=57,61 v=-1,96
+p=51,79 v=31,39
+p=28,89 v=85,35
+p=12,98 v=28,-80
+p=25,61 v=-95,-50
+p=77,84 v=-37,78
+p=50,80 v=66,89
+p=93,32 v=-15,-45
+p=30,4 v=-96,-29
+p=81,95 v=14,-66
+p=23,3 v=42,-16
+p=33,69 v=-96,-10
+p=28,23 v=-43,68
+p=77,25 v=-45,-41
+p=27,96 v=-69,-32
+p=41,15 v=-53,-35
+p=66,81 v=-22,5
+p=5,15 v=13,-95
+p=88,1 v=-59,-26
+p=48,41 v=16,-19
+p=88,75 v=33,46
+p=21,9 v=-64,-86
+p=36,4 v=-16,-95
+p=68,22 v=-5,65
+p=8,43 v=-34,46
+p=71,68 v=-49,-59
+p=37,92 v=-48,-18
+p=59,43 v=-21,-10
+p=69,31 v=30,58
+p=90,77 v=46,-74
+p=42,42 v=-76,20
+p=58,34 v=78,55
+p=18,10 v=33,2
+p=23,92 v=45,-69
+p=23,45 v=-32,27
+p=63,50 v=39,-96
+p=8,72 v=-34,85
+p=22,102 v=-69,26
+p=73,14 v=-45,-38
+p=65,54 v=-51,68
+p=99,29 v=-16,67
+p=29,60 v=15,-19
+p=85,76 v=-54,80
+p=21,23 v=-3,-47
+p=9,37 v=94,-44
+p=99,77 v=48,80
+p=48,47 v=18,56
+p=26,61 v=36,-57
+p=80,58 v=56,90
+p=37,6 v=53,-90
+p=47,15 v=53,60
+p=4,79 v=70,52
+p=35,8 v=31,12
+p=18,8 v=25,-30
+p=80,38 v=33,45
+p=23,26 v=-69,61
+p=10,35 v=-78,-96
+p=53,17 v=48,-34
+p=24,45 v=72,-2
+p=65,75 v=-1,-38
+p=5,72 v=-49,39
+p=63,87 v=-27,-16
+p=0,46 v=-34,73
+p=14,46 v=55,-15
+p=28,70 v=45,92
+p=29,30 v=89,10
+p=98,31 v=-46,-89
+p=1,85 v=-77,82
+p=30,79 v=-43,28
+p=29,70 v=-81,65
+p=51,97 v=13,-25
+p=76,19 v=-23,18
+p=36,83 v=-17,91
+p=52,34 v=-39,-98
+p=35,46 v=-43,55
+p=97,13 v=-99,-26
+p=40,26 v=27,13
+p=18,38 v=89,57
+p=45,57 v=-79,-52
+p=86,76 v=-54,-64
+p=12,38 v=28,55
+p=6,56 v=-86,97
+p=85,100 v=-41,-22
+p=4,34 v=28,-95
+p=89,33 v=-4,-73
+p=82,20 v=-33,-15
+p=98,5 v=31,43
+p=85,81 v=73,88
+p=13,42 v=-90,-49
+p=93,60 v=-91,-64
+p=56,7 v=-5,64
+p=9,5 v=45,76
+p=61,4 v=74,86
+p=23,53 v=-7,3
+p=89,21 v=-38,-74
+p=13,44 v=-86,10
+p=96,62 v=-11,96
+p=5,98 v=-22,3
+p=26,26 v=-73,-93
+p=52,95 v=-5,42
+p=62,50 v=-57,-7
+p=11,2 v=41,-77
+p=23,73 v=-2,-97
+p=34,77 v=-47,-71
+p=91,58 v=99,43
+p=41,74 v=-53,42
+p=75,102 v=55,-81
+p=89,95 v=30,8
+p=76,28 v=-80,12
+p=82,27 v=-43,77
+p=62,63 v=-97,21
+p=94,73 v=-58,14
+p=13,35 v=-47,-46
+p=56,0 v=61,25
+p=94,39 v=11,8
+p=96,53 v=77,-53
+p=23,78 v=-43,-7
+p=24,51 v=-74,-86
+p=77,33 v=60,8
+p=84,71 v=-76,19
+p=78,96 v=82,3
+p=61,92 v=-58,-30
+p=9,75 v=94,-34
+p=89,13 v=7,-26
+p=16,67 v=-25,96
+p=95,43 v=-25,-54
+p=39,62 v=18,-40
+p=41,36 v=17,-65
+p=2,42 v=86,-10
+p=29,54 v=55,-2
+p=51,74 v=-44,92
+p=75,40 v=-36,-96
+p=60,15 v=-93,-84
+p=44,33 v=44,8
+p=88,51 v=85,-94
+p=26,60 v=43,62
+p=94,22 v=-81,-98
+p=4,50 v=-94,-96
+p=87,47 v=-55,3
+p=15,80 v=33,-14
+p=4,48 v=-24,-48
+p=57,36 v=-18,-98
+p=87,12 v=76,63
+p=53,17 v=-91,-81
+p=17,96 v=53,6
+p=91,40 v=95,-46
+p=23,28 v=-55,55
+p=81,7 v=-54,16
+p=62,102 v=-97,-77
+p=42,31 v=80,-41
+p=99,53 v=-72,57
+p=17,29 v=98,58
+p=24,57 v=84,-48
+p=98,101 v=-33,-30
+p=77,82 v=-36,-25
+p=44,8 v=83,18
+p=27,35 v=-27,16
+p=95,58 v=-29,52
+p=87,40 v=60,-91
+p=66,1 v=17,24
+p=17,11 v=63,21
+p=67,77 v=-23,-11
+p=91,30 v=-59,64
+p=22,34 v=7,84
+p=55,90 v=48,29
+p=45,45 v=31,50
+p=12,34 v=65,-86
+p=40,48 v=18,-1
+p=39,42 v=75,11
+p=28,27 v=63,-49
+p=93,44 v=-81,3
+p=8,78 v=-51,-15
+p=6,37 v=-51,-42
+p=73,89 v=-45,23
+p=2,80 v=-23,50
+p=93,37 v=55,-44
+p=16,52 v=-54,35
+p=15,17 v=-33,74
+p=84,37 v=-6,-48
+p=13,47 v=50,-48
+p=88,34 v=-79,-39
+p=16,68 v=50,94
+p=20,78 v=-99,29
+p=100,20 v=77,64
+p=79,2 v=-91,30
+p=52,0 v=-95,-86
+p=4,84 v=79,35
+p=13,74 v=19,-66
+p=57,55 v=-9,-63
+p=21,30 v=19,-94
+p=50,37 v=-66,4
+p=9,56 v=94,95
+p=91,59 v=55,-65
+p=77,15 v=34,-33
+p=5,100 v=81,-26
+p=26,96 v=-34,83
+p=36,64 v=-44,94
+p=37,65 v=-70,51
+p=74,6 v=25,-93
+p=33,78 v=-17,-48
+p=0,33 v=-6,-39
+p=3,55 v=-11,96
+p=32,19 v=-8,-33
+p=60,53 v=-5,-55
+p=75,62 v=56,45
+p=74,71 v=12,-66
+p=50,74 v=-53,91
+p=24,90 v=-19,-57
+p=58,53 v=31,5
+p=13,95 v=-33,20
+p=30,98 v=41,-70
+p=54,78 v=71,-43
+p=78,73 v=26,53
+p=66,30 v=-49,60
+p=81,87 v=-24,-15
+p=28,27 v=-31,11
+p=75,18 v=-89,10
+p=76,82 v=-89,-66
+p=44,65 v=-17,98
+p=17,42 v=-7,-5
+p=75,92 v=-54,32
+p=95,10 v=-28,-76
+p=20,36 v=-22,-62
+p=100,0 v=11,21
+p=37,39 v=5,-46
+p=80,50 v=-63,7
+p=77,28 v=-98,2
+p=61,41 v=-1,-40
+p=88,78 v=95,-17
+p=83,1 v=47,-30
+p=47,67 v=-30,-9
+p=14,81 v=-38,82
+p=40,97 v=-31,76
+p=76,27 v=37,-70
+p=25,73 v=80,35
+p=88,84 v=-33,77
+p=60,71 v=83,35
+p=14,93 v=-3,-25
+p=40,45 v=-35,4
+p=34,35 v=15,19
+p=87,100 v=90,-66
+p=20,90 v=-42,-68
+p=90,44 v=50,-52
+p=43,77 v=31,89
+p=99,81 v=33,-12
+p=28,35 v=58,-37
+p=37,52 v=57,6
+p=48,65 v=-66,23
+p=63,21 v=39,-35
+p=91,77 v=-15,-70
+p=27,28 v=93,-94
+p=18,61 v=-99,38
+p=56,36 v=-98,81
+p=90,75 v=-72,-67
+p=86,21 v=-13,-46
+p=20,88 v=89,-74
+p=17,41 v=-82,-98
+p=28,65 v=45,-72
+p=85,15 v=35,41
+p=39,43 v=-2,-36
+p=93,72 v=-94,91
+p=90,73 v=-64,77
+p=83,43 v=-94,-99
+p=50,59 v=-49,51
+p=58,25 v=13,-36
+p=25,102 v=-44,-54
+p=100,86 v=16,-23
+p=45,42 v=21,-90
+p=9,29 v=-13,18
+p=24,41 v=1,-47
+p=69,33 v=-58,55
+p=80,52 v=52,-2
+p=82,77 v=82,-11
+p=86,78 v=-41,-69
+p=89,58 v=69,-13
+p=12,91 v=-55,-65
+p=69,40 v=-93,59
+p=8,26 v=2,19
+p=21,47 v=19,3
+p=38,20 v=25,-83
+p=20,99 v=54,31
+p=20,74 v=-14,-30
+p=51,83 v=-40,24
+p=61,30 v=-27,-94
+p=84,19 v=-28,69
+p=28,33 v=-65,3
+p=58,91 v=-93,-18
+p=33,78 v=22,92
+p=86,53 v=63,-43
+p=53,79 v=-26,-42
+p=83,16 v=94,56
+p=21,0 v=-64,-35
+p=48,80 v=-97,79
+p=62,18 v=29,71
+p=17,13 v=-69,-36
+p=1,93 v=19,75
+p=7,75 v=41,93
+p=65,61 v=-45,65
+p=56,71 v=92,-63
+p=71,102 v=-53,-21
+p=64,79 v=96,49
+p=40,13 v=-74,-84
+p=28,71 v=93,91
+p=43,68 v=-39,-6
+p=10,40 v=63,55
+p=73,0 v=-97,-82
+p=26,38 v=85,-27
+p=27,94 v=36,-79
+p=1,99 v=-82,-30
+p=66,96 v=-23,31
+p=78,21 v=96,16
+p=10,93 v=-51,-76
+p=76,87 v=78,80
+p=13,20 v=-38,68
+p=31,42 v=-43,5
+p=56,10 v=-53,-33
+p=76,61 v=34,-4
+p=73,2 v=-36,74
+p=93,83 v=15,-19
+p=76,50 v=20,-51
+p=27,53 v=36,-51
+p=93,97 v=50,72
+p=59,22 v=87,21
+p=95,22 v=-29,66
+p=56,35 v=79,10
+p=60,38 v=17,-94
+p=67,41 v=-5,6
+p=97,71 v=-73,35
+p=26,10 v=-73,74
+p=74,71 v=5,64
+p=36,91 v=84,-17
+p=38,91 v=67,33
+p=19,64 v=41,-9
+p=89,15 v=-59,66
+p=5,94 v=94,-27
+p=92,21 v=7,-87
+p=87,64 v=-28,-5
+p=22,6 v=-95,25
+p=59,42 v=-51,-7
+p=50,95 v=88,29
+p=59,91 v=73,-21
+p=52,42 v=-75,56
+p=10,39 v=-30,7
+p=88,79 v=29,-62
+p=31,89 v=-21,-82
+p=43,60 v=4,52
+p=2,76 v=-68,-15
+p=13,71 v=-38,97
+p=93,38 v=1,-95
+p=53,99 v=10,16
+p=94,72 v=-98,30
+p=1,3 v=37,-82
+p=68,78 v=55,18
+p=1,78 v=42,-7
+p=80,84 v=52,-26
+p=75,46 v=-87,-20
+p=71,27 v=95,-39
+p=90,18 v=73,11
+p=99,3 v=62,52
+p=39,88 v=-80,-93
+p=85,32 v=69,-40
+p=72,23 v=-28,-75
+p=22,59 v=98,-7
+p=69,76 v=12,93
+p=56,59 v=30,50
+p=80,92 v=-49,-80
+p=4,40 v=-77,-50
+p=90,60 v=40,-28
+p=6,79 v=9,56
+p=63,47 v=57,-59
+p=33,62 v=22,37
+p=74,27 v=78,70
+p=26,101 v=-43,-49
+p=1,24 v=-29,-38
+p=73,90 v=56,79
+p=5,90 v=-20,-75
+p=16,35 v=94,8
+p=96,93 v=4,58
+p=61,43 v=4,4
+p=13,68 v=76,94
+p=5,29 v=86,-95
+p=32,81 v=39,-85
+p=94,42 v=-37,55
+p=80,20 v=60,22
+p=43,94 v=57,-19
+p=93,4 v=51,-26
+p=12,4 v=62,-58
+p=87,74 v=-98,-64
+p=81,41 v=-26,69
+p=30,54 v=-30,-13
+p=73,4 v=21,-30
+p=68,35 v=-49,-44
+p=47,2 v=19,-70
+p=92,100 v=33,79
+p=81,11 v=73,-83
+p=46,75 v=-62,-69
+p=48,56 v=-13,-56
+p=7,84 v=15,30
+p=92,10 v=28,69
+p=15,31 v=-87,61
+p=95,0 v=33,79
+p=3,61 v=-37,-50
+p=73,95 v=96,20

2024/gareth/main.go

@@ -1,7 +1,7 @@
 package main
 
 import (
-	"aoc2024/day10"
+	"aoc2024/day14"
 	"fmt"
 	"os"
 	"time"
@@ -9,9 +9,9 @@ import (
 
 func main() {
 	start := time.Now()
-	data, _ := os.ReadFile("day10/input.txt")
-	fmt.Printf("part 1: %d\n", day10.Part1(string(data)))
-	fmt.Printf("part 2: %d\n", day10.Part2(string(data)))
+	data, _ := os.ReadFile("day14/input.txt")
+	fmt.Printf("part 1: %d\n", day14.Part1(string(data)))
+	fmt.Printf("part 2: %d\n", day14.Part2(string(data)))
 	elapsed := time.Since(start)
 	fmt.Printf("Execution time: %s\n", elapsed)
 }