updated util packages

.gitignore

@@ -1 +1,2 @@
 .vscode/*
+input.txt

2018/day06/main.go

@@ -6,6 +6,7 @@ import (
 	"math"
 	"strings"
 
+	"github.com/alexchao26/advent-of-code-go/mathutil"
 	"github.com/alexchao26/advent-of-code-go/util"
 )
 
@@ -38,7 +39,7 @@ func part1(input string) int {
 			var coordsToBest [2]int
 			distCounts := map[int]int{} // dedeupe equidistant cells
 			for _, coord := range coords {
-				man := util.ManhattanDistance(r, c, coord[0], coord[1])
+				man := mathutil.ManhattanDistance(r, c, coord[0], coord[1])
 				if man <= bestManhattan {
 					bestManhattan = man
 					coordsToBest = coord
@@ -81,7 +82,7 @@ func part2(input string, dist int) int {
 		for c := boundLeft; c <= boundRight; c++ {
 			point := [2]int{r, c}
 			for _, coord := range coords {
-				coordsToTotalDist[point] += util.ManhattanDistance(point[0], point[1], coord[0], coord[1])
+				coordsToTotalDist[point] += mathutil.ManhattanDistance(point[0], point[1], coord[0], coord[1])
 			}
 			if coordsToTotalDist[point] < dist {
 				area++
@@ -99,8 +100,8 @@ func parseInputCoords(input string) [][2]int {
 		c := strings.Split(l, ", ")
 		if len(c) == 2 {
 			coords = append(coords, [2]int{
-				util.StrToInt(c[0]),
+				mathutil.StrToInt(c[0]),
-				util.StrToInt(c[1]),
+				mathutil.StrToInt(c[1]),
 			})
 		}
 	}

2018/day07/main.go

@@ -7,6 +7,7 @@ import (
 	"sort"
 	"strings"
 
+	"github.com/alexchao26/advent-of-code-go/mathutil"
 	"github.com/alexchao26/advent-of-code-go/util"
 )
 
@@ -100,7 +101,7 @@ func part2(input string, workers, fudgeTime int) int {
 				if len(prereqsCompletionTimes) == 0 {
 					readySteps = append(readySteps, name)
 				} else {
-					earliestScheduleTime := util.MaxInts(prereqsCompletionTimes...)
+					earliestScheduleTime := mathutil.MaxInt(prereqsCompletionTimes...)
 					if earliestScheduleTime <= time {
 						readySteps = append(readySteps, name)
 					}

2018/day08/main.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"strings"
 
+	"github.com/alexchao26/advent-of-code-go/mathutil"
 	"github.com/alexchao26/advent-of-code-go/util"
 )
 
@@ -50,7 +51,7 @@ func parseInput(input string) []int {
 	parsed := make([]int, len(split))
 
 	for i, v := range split {
-		parsed[i] = util.StrToInt(v)
+		parsed[i] = mathutil.StrToInt(v)
 	}
 
 	return parsed

2018/day09/main.go

@@ -6,6 +6,7 @@ import (
 	"strconv"
 	"strings"
 
+	"github.com/alexchao26/advent-of-code-go/mathutil"
 	"github.com/alexchao26/advent-of-code-go/util"
 )
 
@@ -53,13 +54,13 @@ func part1(input string) int {
 		playerTurn %= players
 	}
 
-	return util.MaxInts(playerScores...)
+	return mathutil.MaxInt(playerScores...)
 }
 
 func part2(input string) int {
 	// lazily modify input...
 	split := strings.Split(input, " ")
-	steps := util.StrToInt(split[6]) * 100
+	steps := mathutil.StrToInt(split[6]) * 100
 	split[6] = strconv.Itoa(steps)
 
 	return part1(strings.Join(split, " "))
@@ -67,7 +68,7 @@ func part2(input string) int {
 
 func parseInput(input string) (players int, lastPoints int) {
 	split := strings.Split(input, " ")
-	return util.StrToInt(split[0]), util.StrToInt(split[6])
+	return mathutil.StrToInt(split[0]), mathutil.StrToInt(split[6])
 }
 
 type CircularLinkedListNode struct {

2018/day10/main.go

@@ -7,6 +7,7 @@ import (
 	"strings"
 	"time"
 
+	"github.com/alexchao26/advent-of-code-go/mathutil"
 	"github.com/alexchao26/advent-of-code-go/util"
 )
 
@@ -62,8 +63,8 @@ func parseInputs(input string) (positions [][2]int, velocities [][2]int) {
 		posY := strings.TrimSpace(l[18:24])
 		velX := strings.TrimSpace(l[36:38])
 		velY := strings.TrimSpace(l[40:42])
-		positions = append(positions, [2]int{util.StrToInt(posX), util.StrToInt(posY)})
+		positions = append(positions, [2]int{mathutil.StrToInt(posX), mathutil.StrToInt(posY)})
-		velocities = append(velocities, [2]int{util.StrToInt(velX), util.StrToInt(velY)})
+		velocities = append(velocities, [2]int{mathutil.StrToInt(velX), mathutil.StrToInt(velY)})
 	}
 
 	return positions, velocities

2018/day11/main.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"strings"
 
+	"github.com/alexchao26/advent-of-code-go/mathutil"
 	"github.com/alexchao26/advent-of-code-go/util"
 )
 
@@ -88,7 +89,7 @@ func part2(input string) string {
 }
 
 func parseInputs(input string) int {
-	return util.StrToInt(strings.TrimSpace(input))
+	return mathutil.StrToInt(strings.TrimSpace(input))
 }
 
 func generateGrid(gridSN int) [][]int {

2018/day14/main.go

@@ -6,6 +6,7 @@ import (
 	"strconv"
 	"strings"
 
+	"github.com/alexchao26/advent-of-code-go/mathutil"
 	"github.com/alexchao26/advent-of-code-go/util"
 )
 
@@ -65,7 +66,7 @@ func part2(input string) int {
 func parseInput(input string) int {
 	lines := strings.Split(input, "\n")
 
-	return util.StrToInt(lines[0])
+	return mathutil.StrToInt(lines[0])
 }
 
 func step(recipes []int, elf1, elf2 int) ([]int, int, int) {

2018/day16/main.go

@@ -16,11 +16,9 @@ func main() {
 
 	if part == 1 {
 		ans := part1(util.ReadFile("./input.txt"))
-		util.CopyToClipboard(fmt.Sprintf("%v", ans))
 		fmt.Println("Output:", ans)
 	} else {
 		ans := part2(util.ReadFile("./input.txt"))
-		util.CopyToClipboard(fmt.Sprintf("%v", ans))
 		fmt.Println("Output:", ans)
 	}
 }

2018/day18/main.go

@@ -16,11 +16,9 @@ func main() {
 
 	if part == 1 {
 		ans := part1(util.ReadFile("./input.txt"))
-		util.CopyToClipboard(fmt.Sprintf("%v", ans))
 		fmt.Println("Output:", ans)
 	} else {
 		ans := part2(util.ReadFile("./input.txt"))
-		util.CopyToClipboard(fmt.Sprintf("%v", ans))
 		fmt.Println("Output:", ans)
 	}
 }

2019/day07/part1/main.go

@@ -6,11 +6,13 @@ MakePermutations is in the util package as that will likely be reused
 package main
 
 import (
-	"github.com/alexchao26/advent-of-code-go/util"
 	"fmt"
 	"log"
 	"strconv"
 	"strings"
+
+	"github.com/alexchao26/advent-of-code-go/algos"
+	"github.com/alexchao26/advent-of-code-go/util"
 )
 
 func main() {
@@ -25,7 +27,7 @@ func main() {
 	}
 
 	// Make perms via a util function
-	perms := util.MakePermutations([]int{0, 1, 2, 3, 4})
+	perms := algos.MakePermutations([]int{0, 1, 2, 3, 4})
 
 	// iterate over all perms and run through a single pass of the Amps
 	// if the final output (from Amp E) is higher, update the highestOutput variable

2019/day07/part2/main.go

@@ -6,11 +6,13 @@ MakePermutations is in the util package as that will likely be reused
 package main
 
 import (
-	"github.com/alexchao26/advent-of-code-go/util"
 	"fmt"
 	"log"
 	"strconv"
 	"strings"
+
+	"github.com/alexchao26/advent-of-code-go/algos"
+	"github.com/alexchao26/advent-of-code-go/util"
 )
 
 func main() {
@@ -25,7 +27,7 @@ func main() {
 	}
 
 	// Make perms via a util function
-	perms := util.MakePermutations([]int{5, 6, 7, 8, 9})
+	perms := algos.MakePermutations([]int{5, 6, 7, 8, 9})
 
 	// iterate over all perms and run through a single pass of the Amps
 	// if the final output (from Amp E) is higher, update the highestOutput variable

2019/day11/part2/main.go

@@ -9,11 +9,14 @@ Draw function generates a string to display in terminal
 package main
 
 import (
-	"github.com/alexchao26/advent-of-code-go/util"
 	"fmt"
 	"log"
 	"strconv"
 	"strings"
+
+	"github.com/alexchao26/advent-of-code-go/algos"
+	"github.com/alexchao26/advent-of-code-go/mathutil"
+	"github.com/alexchao26/advent-of-code-go/util"
 )
 
 func main() {
@@ -79,7 +82,7 @@ func Draw(mapCoordsToColor map[string]int) string {
 	}
 
 	// Determine the bounds of the grid
-	edgeLength := 2 * util.MaxInts(-lowY, -lowX, highY, highX)
+	edgeLength := 2 * mathutil.MaxInt(-lowY, -lowX, highY, highX)
 
 	grid := make([][]string, edgeLength)
 	for i := 0; i < edgeLength; i++ {
@@ -108,7 +111,7 @@ func Draw(mapCoordsToColor map[string]int) string {
 	// trim off due to making the initial grid too large
 	grid = trim(grid)
 	// rotate it because of how I coded up the robot's coordinates :/
-	grid = util.RotateGrid(grid)
+	grid = algos.RotateStringGrid(grid)
 	// retrim
 	grid = trim(grid)
 

2019/day15/part1/main.go

@@ -9,12 +9,15 @@ Robot struct houses an Intcode computer and its RecursiveMove method populates a
 package main
 
 import (
-	"github.com/alexchao26/advent-of-code-go/util"
 	"fmt"
 	"log"
 	"math"
 	"strconv"
 	"strings"
+
+	"github.com/alexchao26/advent-of-code-go/algos"
+	"github.com/alexchao26/advent-of-code-go/mathutil"
+	"github.com/alexchao26/advent-of-code-go/util"
 )
 
 func main() {
@@ -333,7 +336,7 @@ func Draw(mapCoordsToType map[string]int) [][]int {
 	}
 
 	// Determine the bounds of the grid
-	edgeLength := 2 * util.MaxInts(-lowY, -lowX, highY, highX)
+	edgeLength := 2 * mathutil.MaxInt(-lowY, -lowX, highY, highX)
 
 	grid := make([][]int, edgeLength)
 	for i := 0; i < edgeLength; i++ {
@@ -359,7 +362,7 @@ func Draw(mapCoordsToType map[string]int) [][]int {
 	// trim off due to making the initial grid too large
 	grid = trim(grid)
 	// rotate it because of how I coded up the robot's coordinates :/
-	grid = util.RotateGridInts(grid)
+	grid = algos.RotateIntGrid(grid)
 	// retrim
 	grid = trim(grid)
 

2019/day15/part2/main.go

@@ -12,11 +12,14 @@ Robot struct houses an Intcode computer and its RecursiveMove method populates a
 package main
 
 import (
-	"github.com/alexchao26/advent-of-code-go/util"
 	"fmt"
 	"log"
 	"strconv"
 	"strings"
+
+	"github.com/alexchao26/advent-of-code-go/algos"
+	"github.com/alexchao26/advent-of-code-go/mathutil"
+	"github.com/alexchao26/advent-of-code-go/util"
 )
 
 func main() {
@@ -387,7 +390,7 @@ func Draw(mapCoordsToType map[string]int) [][]int {
 	}
 
 	// Determine the bounds of the grid
-	edgeLength := 2 * util.MaxInts(-lowY, -lowX, highY, highX)
+	edgeLength := 2 * mathutil.MaxInt(-lowY, -lowX, highY, highX)
 
 	grid := make([][]int, edgeLength)
 	for i := 0; i < edgeLength; i++ {
@@ -413,7 +416,7 @@ func Draw(mapCoordsToType map[string]int) [][]int {
 	// trim off due to making the initial grid too large
 	grid = trim(grid)
 	// rotate it because of how I coded up the robot's coordinates :/
-	grid = util.RotateGridInts(grid)
+	grid = algos.RotateIntGrid(grid)
 	// retrim
 	grid = trim(grid)
 

2020/day01/main.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"strings"
 
+	"github.com/alexchao26/advent-of-code-go/mathutil"
 	"github.com/alexchao26/advent-of-code-go/util"
 )
 
@@ -60,7 +61,7 @@ func parseInputs(input string) []int {
 
 	nums := []int{}
 	for _, n := range split {
-		nums = append(nums, util.StrToInt(n))
+		nums = append(nums, mathutil.StrToInt(n))
 	}
 
 	return nums

2020/day07/main.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"strings"
 
+	"github.com/alexchao26/advent-of-code-go/mathutil"
 	"github.com/alexchao26/advent-of-code-go/util"
 )
 
@@ -58,7 +59,7 @@ func parseInput(input string) map[string]map[string]int {
 				continue
 			}
 			parts := strings.Split(content, " ")
-			graph[color][parts[1]+" "+parts[2]] = util.StrToInt(parts[0])
+			graph[color][parts[1]+" "+parts[2]] = mathutil.StrToInt(parts[0])
 		}
 	}
 	return graph

2020/day10/main.go

@@ -29,7 +29,7 @@ func main() {
 
 func part1(input string) int {
 	nums := parseInput(input)
-	nums = append(nums, util.MaxInts(nums...)+3)
+	nums = append(nums, mathutil.MaxInt(nums...)+3)
 	sort.Ints(nums)
 
 	var oneDiff, threeDiff int
@@ -51,7 +51,7 @@ func part1(input string) int {
 
 func part2(input string) int {
 	nums := parseInput(input)
-	nums = append(nums, util.MaxInts(nums...)+3)
+	nums = append(nums, mathutil.MaxInt(nums...)+3)
 	sort.Ints(nums)
 
 	// return dynamicProgramming(input)
@@ -63,7 +63,7 @@ func parseInput(input string) []int {
 
 	lines := strings.Split(input, "\n")
 	for _, l := range lines {
-		ans = append(ans, util.StrToInt(l))
+		ans = append(ans, mathutil.StrToInt(l))
 	}
 
 	return ans
@@ -109,7 +109,7 @@ func makeMemoKey(nums []int, lastJolt int) string {
 
 func dynamicProgramming(input string) int {
 	nums := parseInput(input)
-	nums = append(nums, util.MaxInts(nums...)+3, 0)
+	nums = append(nums, mathutil.MaxInt(nums...)+3, 0)
 	sort.Ints(nums)
 
 	// initialize table with "1 way" to get to zero jolts

2020/day11/main.go

@@ -44,7 +44,7 @@ func parseInput(input string) []int {
 
 	lines := strings.Split(input, "\n")
 	for _, l := range lines {
-		ans = append(ans, util.StrToInt(l))
+		ans = append(ans, mathutil.StrToInt(l))
 	}
 
 	return ans

2020/day12/main.go

@@ -44,7 +44,7 @@ func parseInput(input string) []int {
 
 	lines := strings.Split(input, "\n")
 	for _, l := range lines {
-		ans = append(ans, util.StrToInt(l))
+		ans = append(ans, mathutil.StrToInt(l))
 	}
 
 	return ans

2020/day13/main.go

@@ -44,7 +44,7 @@ func parseInput(input string) []int {
 
 	lines := strings.Split(input, "\n")
 	for _, l := range lines {
-		ans = append(ans, util.StrToInt(l))
+		ans = append(ans, mathutil.StrToInt(l))
 	}
 
 	return ans

2020/day14/main.go

@@ -44,7 +44,7 @@ func parseInput(input string) []int {
 
 	lines := strings.Split(input, "\n")
 	for _, l := range lines {
-		ans = append(ans, util.StrToInt(l))
+		ans = append(ans, mathutil.StrToInt(l))
 	}
 
 	return ans

2020/day15/main.go

@@ -44,7 +44,7 @@ func parseInput(input string) []int {
 
 	lines := strings.Split(input, "\n")
 	for _, l := range lines {
-		ans = append(ans, util.StrToInt(l))
+		ans = append(ans, mathutil.StrToInt(l))
 	}
 
 	return ans

2020/day16/main.go

@@ -44,7 +44,7 @@ func parseInput(input string) []int {
 
 	lines := strings.Split(input, "\n")
 	for _, l := range lines {
-		ans = append(ans, util.StrToInt(l))
+		ans = append(ans, mathutil.StrToInt(l))
 	}
 
 	return ans

2020/day17/main.go

@@ -44,7 +44,7 @@ func parseInput(input string) []int {
 
 	lines := strings.Split(input, "\n")
 	for _, l := range lines {
-		ans = append(ans, util.StrToInt(l))
+		ans = append(ans, mathutil.StrToInt(l))
 	}
 
 	return ans

2020/day18/main.go

@@ -44,7 +44,7 @@ func parseInput(input string) []int {
 
 	lines := strings.Split(input, "\n")
 	for _, l := range lines {
-		ans = append(ans, util.StrToInt(l))
+		ans = append(ans, mathutil.StrToInt(l))
 	}
 
 	return ans

2020/day19/main.go

@@ -44,7 +44,7 @@ func parseInput(input string) []int {
 
 	lines := strings.Split(input, "\n")
 	for _, l := range lines {
-		ans = append(ans, util.StrToInt(l))
+		ans = append(ans, mathutil.StrToInt(l))
 	}
 
 	return ans

2020/day20/main.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"strings"
 
+	"github.com/alexchao26/advent-of-code-go/mathutil"
 	"github.com/alexchao26/advent-of-code-go/util"
 )
 
@@ -44,7 +45,7 @@ func parseInput(input string) []int {
 
 	lines := strings.Split(input, "\n")
 	for _, l := range lines {
-		ans = append(ans, util.StrToInt(l))
+		ans = append(ans, mathutil.StrToInt(l))
 	}
 
 	return ans

2020/day21/main.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"strings"
 
+	"github.com/alexchao26/advent-of-code-go/mathutil"
 	"github.com/alexchao26/advent-of-code-go/util"
 )
 
@@ -44,7 +45,7 @@ func parseInput(input string) []int {
 
 	lines := strings.Split(input, "\n")
 	for _, l := range lines {
-		ans = append(ans, util.StrToInt(l))
+		ans = append(ans, mathutil.StrToInt(l))
 	}
 
 	return ans

2020/day22/main.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"strings"
 
+	"github.com/alexchao26/advent-of-code-go/mathutil"
 	"github.com/alexchao26/advent-of-code-go/util"
 )
 
@@ -44,7 +45,7 @@ func parseInput(input string) []int {
 
 	lines := strings.Split(input, "\n")
 	for _, l := range lines {
-		ans = append(ans, util.StrToInt(l))
+		ans = append(ans, mathutil.StrToInt(l))
 	}
 
 	return ans

2020/day23/main.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"strings"
 
+	"github.com/alexchao26/advent-of-code-go/mathutil"
 	"github.com/alexchao26/advent-of-code-go/util"
 )
 
@@ -44,7 +45,7 @@ func parseInput(input string) []int {
 
 	lines := strings.Split(input, "\n")
 	for _, l := range lines {
-		ans = append(ans, util.StrToInt(l))
+		ans = append(ans, mathutil.StrToInt(l))
 	}
 
 	return ans

2020/day24/main.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"strings"
 
+	"github.com/alexchao26/advent-of-code-go/mathutil"
 	"github.com/alexchao26/advent-of-code-go/util"
 )
 
@@ -44,7 +45,7 @@ func parseInput(input string) []int {
 
 	lines := strings.Split(input, "\n")
 	for _, l := range lines {
-		ans = append(ans, util.StrToInt(l))
+		ans = append(ans, mathutil.StrToInt(l))
 	}
 
 	return ans

2020/day25/main.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"strings"
 
+	"github.com/alexchao26/advent-of-code-go/mathutil"
 	"github.com/alexchao26/advent-of-code-go/util"
 )
 
@@ -44,7 +45,7 @@ func parseInput(input string) []int {
 
 	lines := strings.Split(input, "\n")
 	for _, l := range lines {
-		ans = append(ans, util.StrToInt(l))
+		ans = append(ans, mathutil.StrToInt(l))
 	}
 
 	return ans

algos/permutations.go

@@ -1,4 +1,4 @@
-package util
+package algos
 
 // MakePermutations will make all permutations of the numbers input
 // returns a pointer to avoid copying a large number of permutations

algos/rotate-grid.go

@@ -1,8 +1,8 @@
-package util
+package algos
 
 // RotateGrid returns the inputted grid, rotated counterclockwise
 // call it multiple times for 180, & 270 degree rotations
-func RotateGrid(grid [][]string) [][]string {
+func RotateStringGrid(grid [][]string) [][]string {
 	rotated := make([][]string, len(grid[0]))
 	for i := range rotated {
 		rotated[i] = make([]string, len(grid))
@@ -17,7 +17,7 @@ func RotateGrid(grid [][]string) [][]string {
 }
 
 // RotateGridInts will transpose a 2D array of ints
-func RotateGridInts(grid [][]int) [][]int {
+func RotateIntGrid(grid [][]int) [][]int {
 	rotated := make([][]int, len(grid[0]))
 	for i := range rotated {
 		rotated[i] = make([]int, len(grid))

algos/sliding-window.go

@@ -0,0 +1,25 @@
+package algos
+
+// SlidingWindowSum returns the left and right indices of a window within the
+// nums slice, where all numbers in the slice [left:right] sum up to targetSum
+// It also returns a boolean indicating if a valid window is found
+func SlidingWindowSum(nums []int, targetSum int) (leftIndex, rightIndex int, found bool) {
+	var left, right, sum int
+	for right < len(nums) {
+		switch {
+		case left == right:
+			sum += nums[right]
+			right++
+		case sum > targetSum:
+			sum -= nums[left]
+			left++
+		case sum < targetSum:
+			sum += nums[right]
+			right++
+		}
+		if sum == targetSum {
+			return left, right, true
+		}
+	}
+	return 0, 0, false
+}

algos/sliding-window_test.go

@@ -0,0 +1,36 @@
+package algos
+
+import "testing"
+
+func TestSlidingWindowSum(t *testing.T) {
+	type args struct {
+		nums      []int
+		targetSum int
+	}
+	tests := []struct {
+		name           string
+		args           args
+		wantLeftIndex  int
+		wantRightIndex int
+		wantFound      bool
+	}{
+		{"found 1", args{[]int{-1, 23, 12, 14, 3, 4}, 21}, 3, 6, true},
+		{"found 2", args{[]int{-1, 23, 12, 14, 3, 4, 59}, 21}, 3, 6, true},
+		{"not found 1", args{[]int{0, 1, 2, 3, 4, 5, 6}, 45}, 0, 0, false},
+		{"not found 2", args{[]int{0, 1, 2, 3, 4, 5, 6}, -34}, 0, 0, false},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			gotLeftIndex, gotRightIndex, gotFound := SlidingWindowSum(tt.args.nums, tt.args.targetSum)
+			if gotLeftIndex != tt.wantLeftIndex {
+				t.Errorf("SlidingWindowSum() gotLeftIndex = %v, want %v", gotLeftIndex, tt.wantLeftIndex)
+			}
+			if gotRightIndex != tt.wantRightIndex {
+				t.Errorf("SlidingWindowSum() gotRightIndex = %v, want %v", gotRightIndex, tt.wantRightIndex)
+			}
+			if gotFound != tt.wantFound {
+				t.Errorf("SlidingWindowSum() gotFound = %v, want %v", gotFound, tt.wantFound)
+			}
+		})
+	}
+}

algos/twosum.go

@@ -0,0 +1,27 @@
+package algos
+
+// TwoSum returns the two numbers found within a slice that add up to
+// the input target, and a boolean to check if the sum is found or not
+func TwoSum(nums []int, target int) (num1 int, num2 int, found bool) {
+	seen := make(map[int]bool, len(nums))
+
+	for _, v := range nums {
+		if seen[target-v] {
+			return target - v, v, true
+		}
+		seen[v] = true
+	}
+
+	return 0, 0, false
+}
+
+// ThreeSum returns the three values within a slice that sum to the
+// target input and a boolean stating if a match was found
+func ThreeSum(nums []int, target int) (int, int, int, bool) {
+	for i, v := range nums {
+		if num1, num2, found := TwoSum(nums[i+1:], target-v); found {
+			return v, num1, num2, true
+		}
+	}
+	return 0, 0, 0, false
+}

algos/twosum_test.go

@@ -0,0 +1,76 @@
+package algos
+
+import "testing"
+
+func TestTwoSum(t *testing.T) {
+	type args struct {
+		nums   []int
+		target int
+	}
+	tests := []struct {
+		name      string
+		args      args
+		wantNum1  int
+		wantNum2  int
+		wantFound bool
+	}{
+		{"found 1", args{[]int{0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10}, 6}, 2, 4, true},
+		{"found 2", args{[]int{0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10}, 17}, 8, 9, true},
+		{"not found 1", args{[]int{0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10}, 62}, 0, 0, false},
+		{"not found 2", args{[]int{0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10}, -12}, 0, 0, false},
+		{"found 3", args{[]int{0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, -13}, -12}, 1, -13, true},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			gotNum1, gotNum2, gotFound := TwoSum(tt.args.nums, tt.args.target)
+			if gotNum1 != tt.wantNum1 {
+				t.Errorf("TwoSum() gotNum1 = %v, want %v", gotNum1, tt.wantNum1)
+			}
+			if gotNum2 != tt.wantNum2 {
+				t.Errorf("TwoSum() gotNum2 = %v, want %v", gotNum2, tt.wantNum2)
+			}
+			if gotFound != tt.wantFound {
+				t.Errorf("TwoSum() gotFound = %v, want %v", gotFound, tt.wantFound)
+			}
+		})
+	}
+}
+
+func TestThreeSum(t *testing.T) {
+	type args struct {
+		nums   []int
+		target int
+	}
+	tests := []struct {
+		name  string
+		args  args
+		want  int
+		want1 int
+		want2 int
+		want3 bool
+	}{
+		{"found 1", args{[]int{0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10}, 6}, 0, 2, 4, true},
+		{"found 2", args{[]int{0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10}, 17}, 0, 8, 9, true},
+		{"not found 1", args{[]int{0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10}, 62}, 0, 0, 0, false},
+		{"not found 2", args{[]int{0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10}, -12}, 0, 0, 0, false},
+		{"found 3", args{[]int{0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, -13}, -12}, 0, 1, -13, true},
+		{"found 3", args{[]int{0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10}, 27}, 8, 9, 10, true},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got, got1, got2, got3 := ThreeSum(tt.args.nums, tt.args.target)
+			if got != tt.want {
+				t.Errorf("ThreeSum() got = %v, want %v", got, tt.want)
+			}
+			if got1 != tt.want1 {
+				t.Errorf("ThreeSum() got1 = %v, want %v", got1, tt.want1)
+			}
+			if got2 != tt.want2 {
+				t.Errorf("ThreeSum() got2 = %v, want %v", got2, tt.want2)
+			}
+			if got3 != tt.want3 {
+				t.Errorf("ThreeSum() got3 = %v, want %v", got3, tt.want3)
+			}
+		})
+	}
+}

mathutil/distances.go

@@ -1,4 +1,4 @@
-package util
+package mathutil
 
 import (
 	"math"

mathutil/math.go

@@ -0,0 +1,37 @@
+package mathutil
+
+import (
+	"fmt"
+	"strconv"
+)
+
+func MaxInt(nums ...int) int {
+	maxNum := nums[0]
+	for _, v := range nums {
+		if v > maxNum {
+			maxNum = v
+		}
+	}
+	return maxNum
+}
+func MinInt(nums ...int) int {
+	minNum := nums[0]
+	for _, v := range nums {
+		if v < minNum {
+			minNum = v
+		}
+	}
+	return minNum
+}
+
+func StrToInt(in string) int {
+	num, err := strconv.Atoi(in)
+	if err != nil {
+		panic(fmt.Sprintf("converting string to number: %s", err))
+	}
+	return num
+}
+
+func IntToStr(in int) string {
+	return strconv.Itoa(in)
+}

mathutil/primes.go

@@ -1,4 +1,4 @@
-package util
+package mathutil
 
 import (
 	"math"

mathutil/primes_test.go

@@ -1,4 +1,4 @@
-package util
+package mathutil
 
 import (
 	"fmt"

scripts/template/template.go

@@ -104,7 +104,7 @@ func parseInput(input string) []int {
 
 	lines := strings.Split(input, "\n")
 	for _, l := range lines {
-		ans = append(ans, util.StrToInt(l))
+		ans = append(ans, mathutil.StrToInt(l))
 	}
 
 	return ans

util/MaxInts.go

@@ -1,12 +0,0 @@
-package util
-
-// MaxInts takes a variable number of integers and returns the largest one
-func MaxInts(nums ...int) int {
-	maxNum := nums[0]
-	for _, v := range nums {
-		if v > maxNum {
-			maxNum = v
-		}
-	}
-	return maxNum
-}

util/ReadFile.go

@@ -3,7 +3,6 @@ package util
 import (
 	"io/ioutil"
 	"path"
-	"path/filepath"
 	"runtime"
 	"strings"
 )
@@ -31,12 +30,3 @@ func ReadFile(pathFromCaller string) string {
 	strContent := string(content)
 	return strings.TrimRight(strContent, "\n")
 }
-
-// Dirname is a port of __dirname in node
-func Dirname() string {
-	_, filename, _, ok := runtime.Caller(1)
-	if !ok {
-		panic("getting calling function")
-	}
-	return filepath.Dir(filename)
-}

util/StrToInt.go

@@ -1,14 +0,0 @@
-package util
-
-import (
-	"fmt"
-	"strconv"
-)
-
-func StrToInt(in string) int {
-	num, err := strconv.Atoi(in)
-	if err != nil {
-		panic(fmt.Sprintf("converting string to number: %s", err))
-	}
-	return num
-}