chore: add hackerrank solutions

aoc2023/day21/example.txt

@@ -0,0 +1,11 @@
+...........
+.....###.#.
+.###.##..#.
+..#.#...#..
+....#.#....
+.##..S####.
+.##..#...#.
+.......##..
+.##.#.####.
+.##..##.##.
+...........

aoc2023/day21/input.txt

@@ -0,0 +1,131 @@
+...................................................................................................................................
+.#.......#..#...#.......#......#....#..#...#...#....#.#..........................................#...............#..........#......
+.............##..................#......#.#....#.......................##..#........................#......#..........#............
+......#..........................#....#.....#.............#................##....#.#.............#.........#.##...........#........
+.#................#............................#...........................#..##.....#..................#..##..#.#.........##......
+.....#.............#.....##.............##..........#...........#.............#.....#...........#.#.......#....#......#..........#.
+........#....................#....#.#.#......##........#...........#...........#..........#...#..........#......................#..
+.........#.#...#.......#........#........##...#...#..##........................................##...#.#........................#...
+......#.....#..#..#.#..#..............#...#..#.....#...........#.....#........#.#...........#...........#.#...............#.....#..
+...........#.......####..#.#..............##................#.#.#.....................##.....................#...#..............#..
+......###...#......#................##...#...#....#...........#...#..............#.........#..#..................................#.
+...............#..##..........#...........................##......#.##.........................#..#.#...........#.#...........#....
+...##........#...#...#...##...##...........#..#...................#...................#.#..#.........#.......#..#...........##...#.
+................#.....#..##......#.....#.....##............#..#..........##...........................#.#.......##.....#.....#.....
+.#..#.......#.#...#..##.....#............................#......#...#....#................#.#..#.....#.......##................#...
+...............#.....#........................#..........#.....#..............................................#..................#.
+.....#......#..........................................#....................................#..#.......#.#..#......#.#....#..##....
+............##............#.......###.......................#..#....#......................................#..#.........#..........
+..#...............#.....#...#...#......................#...#.#..............................#.#..#.#.....#.#.#..#....#.....#...##..
+.#.............................##.................#.......#.......##....#....................#.....#.#........#.....#........#.....
+.#....##...................##.....#.#..............#.#....#....#..#....#......#..........#.....##............#....#.............##.
+.........#....#.....#..#.........#....#.#..........#...#...#.......#....#..##.......................#.#..#........#..#....#..#.#...
+..#..................#.......#..#.#..............##.......#........#..............#.........#..#....#......#..#..........#.........
+........#.....#......#.....#......#...#.......#....#.......#.#..#................#....................##.............#.......#.....
+..#.................#..............#...........................................#.....#..................#...#.#..................#.
+.......#......#.....#...........................#.....#..................#.....................#.....#.#......#........#.#.......#.
+..#.#.#...................#...#..#................#....#.......#......................#...............#.........##...#.#.....###...
+.....#...#....##....#........####...........#.................#...#...........................................#..............##....
+..##.#..#.#..........#.#.#..#................................#..#.............#..#......#...........................#.##...........
+..............#.............................##........#..##........................#.............................#........#........
+........#.........#........#..#........#..#........#...#.#........#...........#.........................#.#..........#...#......#..
+.........##.....#........#.....................#..#.............#.....#........#....................#....#.#.#......#.....#........
+......................#...................####..#.........#....#.........#...........#..................#..#.................#.....
+..#.........#...#.....##................##.##....#.....#....#..............................#..#.............#..#...................
+..........##......#..#..............#.#....#......#................#.....#....#..............#..................#..................
+.#.#..####...#....................#.#.#.....#...#...................#....#.#.....#.#.......#.#...........#......#.#................
+.......#.........#..#.#..............###.......#....#.........................#.......#.###...#............#....#.#..#....###.#....
+........#....#...#......#.................#..........................#.........................#...........##.............#.#......
+.#..............#.....................#......#.............##............#..#..........#...................#...#....#..............
+......#..#..#.#...............#........###.......#.#...........#...........#.#.........#..#.....................#......#..#.#......
+.....#...............#.........#....#..........#.......#.......#......#...#..##.....#.....#........#.#.......#.......#..#...#......
+..#............#.....................#...#.......#....###...........#.....#.#.................#................#.........#..##.#...
+..............................#.....#..................................#.....##...............#.......#.........#.....#....##......
+..#...##...#...#..............#.................##..#......#.................#....#......#...#...#......#..........................
+.........#....#..............#........#..#...............#....#...#.....#..#......#.........#.......#.#..#........#...........#....
+........#..#....................#.........#...##.#.#..............#......#.#..........##...##....#......................#..........
+.##..#....#....#.......##......#............#..#......#.....##..................#####..#...#......#.#...#..........#.#.....#..#....
+..#...........#....................#.......#......#.........#...............#......#........##........#.................#.....#.#..
+..#....#.#...............#.#.........................#.............####..............................##................###.........
+.....#.......................................#....#...##...#.......#.......#.....#.##..##.................#.....................##.
+.........#...........#..#..##.#..........#..#.........#..#.....#...................................##....#...............#..#.#....
+.....#..#...........##............#........#..................#............#..........#..........#..#...........#..................
+............................#.........#...............#..................#.#....#.#..#........#.....#...........#...........#......
+................#...##.#....#..##..........#.#........##.#..#..#.....................#....#.................#.#...............#....
+.#.....#..............#.#..........#..#........#...............#..#.#..##..#.#.#.........................#.................#.......
+....#..............#................#.....#..#.......#..#.#.........#..........#..........#.....#..........##.....#............#...
+..............##...........#.......#......#..................#.......#.....#.#...#...............#.#........#......#............#..
+................#.....#....#........#....#.......#.#.##.....#...#..#.##...#................#.#.....#....#.............#............
+...........#.#.##..####.....#....#.#...#.#...........#...#.......................#.#....#.....#..#................###..............
+...................#....#..........#.#..##.....#..#..#......###............#..#...........#....#......#............................
+...........................................#.......#..............#.##.......##.......#...#.....#.#..#.....#..###..................
+............###........#.......#.#....#.....#....#..#........#.........##....#.....#..........#......#............#..#.#...........
+............#..........#................##.#..............#.....#................#....................................#..#.........
+...........#.....#.....................#...#.....#.......#..........#....#.....###.....##.#.##.#.....#......#......#.......#.......
+.....................#..#.....#...##.....#..#...........#....#....##............##.................##............##................
+.................................................................S.................................................................
+........#.#........#..........#.....#......#........#.#............#.#.........##...#............#...#.....#...........#.....#.....
+..................##.......#......#..#..................#..##......#.........#...#.........#............#....#...........##........
+..................#...........#.##.......#..............#....................#.#....#...##...#.....#.......#..#.....##.............
+...........#....#....##...#................................#.........#.................#....#.......................#...#..........
+.............#.#.#.....#.#...#.......#.#...........#....#.#.........#........##......#.......#.......##...#..........#.##..........
+...........##.#....#....#..#.....#...............#......................#...........#.....#...........#.#.......#..................
+.#.......................#.#...##.#....#.#...........#.#....##.##......#........................##....#.#....#.....................
+...#..................#.#...........##....###.................#....................##......#.....#............#.##....#.......##...
+.#..................####...#.#..#.##.#...####...#......#....................#..........................#....#......................
+.....#..........#.....#.#...............#.........##...#......#.#.....#...........#.....#............##......#.....#...............
+......#........#....#..#............................###.#...##........#........#.................#..#........#...............##....
+......................#.........................##....#...#..............#..#............#.#....#......##.#......#.........##......
+..................#....#...#.#.......#..............#..#..#...#.......#...#.....#.....#...............#.#.#...............#........
+...#...##......................##..##...........#......#.............#............#...........##.......#....#......................
+.............................##...........##...#...#.....#....#.......#.#..#.....##...............#..#.#......#..............##....
+...#..#.#...#.......#..................#............#....#.#.##.#.........#......#........#..#..........#....##...........#....#...
+.....#.............................#......#.#.....#.##.#.................#.........#..#..#.#.#........................#.#.......#..
+....#........#........#....#.#.#.....#.##............###.#..........#...##......#........##...#.........#.............#........#...
+..#..............................#.............................#......#...................#...#......#.............#...............
+.......#...#...............#.................##....................#....##.......#....##....##...#..................#..............
+.........................#...#..#.....##.............#...##.......#.....#...#..............#.....#.#.#..#........................#.
+......#.......##.#.............#....................#...#...........#...#..##....#.....#............#...........#........#.........
+...#....#...#......#........................#.....#.........#......#........#.....#.#...........#.#..............#......#....#.....
+........#..........#...................#...........##.#..#...#................#....##.............#................#....#..........
+........#.......#....#.............#..........#...................#.#....#.#........#..#..............................#..........#.
+............#........#....................#.#.........#......#.............#................#...#.............#....#...............
+..#..............................#..#....##.....#......................##...#..#.........#......#......................#...#...#.#.
+.##....#.............#...........##..................#...#..............#.......#................................#.........#.......
+.....#......#.#.....##...........#.....#.......#..........##..#.............#.#.........#.#.#.............##........#......#..#....
+.......#.......#.#.#..#......................#....#............##....#...........#.........................#......#................
+.........##.........#..............#.#.#....#...#.......#.................................#..##..................##.###.##...#.....
+......................#...#.#.......#..#.#..........#........#.......#.................#..................................#........
+....##........#.........#.........................#................#......#...#.....#..................................#..#.#......
+...##..............#..................#...#......#........###..#.......#..........#..............................#......#..........
+.#.#.#....#..........#......#.#.........#.....#...............................#.....#.#............#....#........#.............#...
+........#.........#.........#......................#..#......##.....#..#..........................#......##....#......##.##.....#..
+.##...#.......#.#....#..#.#...................#.........#....#...........#.....#.........#............##......#............#.......
+.##..#.........#..........#.#.................................#.#.#...............................#............#......##...#.#.....
+......#........#..#...#............#..............#............#......##.....#.................................#......#.#.....#....
+..........#........#...........#....................................#.....#...............................#............##....#.##..
+........#.............#..#......##..................#.............#..#...#.#.....#...#...............#........................#....
+....#...............#..........#....#...........................#....##.##...................#.#.......#...#.##....#........##..#..
+......#.....#..#..........###...#.................####.###..........#...........#..........#......#............................#...
+.#...#......#........#..#............##...............#.##......#...#.....#....................#.........#............#...#........
+................##...................#.##..............#...#..#.......#.......###........#..#..#........#...##.....................
+..............#....#..#..#.............##..............#................................#.....#..#....###.##..............#........
+..#..............#........................................#..........#.....#..................#............#..#....................
+.........#...#.....#...#...##...........#.###............##...#........#......................##......#....#.......#...............
+....#....#.....#.......#......................................#.#.#....#..#..#..........#...................#........#...#.........
+..#..#..................#..............#...#..#.........#......#....#.#................##..........#..#................#...........
+...#...................#...........#....#...#.............##...#.......#.#..........#..#...............#....#....#.............#...
+.......................##.#.#..##........#....#.........#.#.#.....##..............#.......#.......##.#..........#.#................
+.....#..#..................#..##....#.......#.............#...#.....#.............#.............#.#...............#.....##......##.
+...#.#.....#..........#.#............#..#..........................##.............#....#.......#.#...#...#....................#.#..
+............##.#............#....#....#....#..##...#...............................#...#...#.........#.......................##.##.
+....#.#...............#...#.......#............#..#...........................#..............#..........#....#...#...#..#...#....#.
+.......#..#..#.#..#......#..........................#...............#.........#...........#................#..#...#................
+...#..#...#.....#.#.......#....................................................#........#..........#.#...#......#..........#.......
+..#...#.......#..#..............#.#...#.....#...#....#............#..........##...#.........##.............#.......................
+...#.............#...#....#...#.....#.#.#..............#..........#........#........##...........#..#.#......................#.....
+.#.......#.................#...............#..........#.....................#.....#............#......##....#.....#...#....###.....
+...##...........#..........#.#........#............#..#.#........................#.....##............#...##.#.......#.##....#......
+...........#........#...........#.......#......#...#.....#............................#........#..#................#...#....##.....
+...##.##.........#.####..#............#..#.....#.......................#......#..........#.#..#.#....##........#....#.....#..#..##.
+...................................................................................................................................

aoc2023/day21/main.go

@@ -0,0 +1,30 @@
+package main
+
+import (
+	"bufio"
+	_ "embed"
+	"fmt"
+
+	aoc "go.sour.is/advent-of-code"
+)
+
+// var log = aoc.Log
+
+func main() { aoc.MustResult(aoc.Runner(run)) }
+
+type result struct {
+	valuePT1 int
+	valuePT2 int
+}
+
+func (r result) String() string { return fmt.Sprintf("%#v", r) }
+
+func run(scan *bufio.Scanner) (*result, error) {
+
+	for scan.Scan() {
+		_ = scan.Text()
+
+	}
+
+	return &result{}, nil
+}

aoc2023/day21/main_test.go

@@ -0,0 +1,41 @@
+package main
+
+import (
+	"bufio"
+	"bytes"
+	"testing"
+
+	_ "embed"
+
+	"github.com/matryer/is"
+)
+
+//go:embed example.txt
+var example []byte
+
+//go:embed input.txt
+var input []byte
+
+func TestExample(t *testing.T) {
+	is := is.New(t)
+	scan := bufio.NewScanner(bytes.NewReader(example))
+
+	result, err := run(scan)
+	is.NoErr(err)
+
+	t.Log(result)
+	is.Equal(result.valuePT1, 0)
+	is.Equal(result.valuePT2, 0)
+}
+
+func TestSolution(t *testing.T) {
+	is := is.New(t)
+	scan := bufio.NewScanner(bytes.NewReader(input))
+
+	result, err := run(scan)
+	is.NoErr(err)
+
+	t.Log(result)
+	is.Equal(result.valuePT1, 0)
+	is.Equal(result.valuePT2, 0)
+}

aoc2024/day01/main.go

@@ -0,0 +1,30 @@
+package main
+
+import (
+	"bufio"
+	_ "embed"
+	"fmt"
+
+	aoc "go.sour.is/advent-of-code"
+)
+
+// var log = aoc.Log
+
+func main() { aoc.MustResult(aoc.Runner(run)) }
+
+type result struct {
+	valuePT1 int
+	valuePT2 int
+}
+
+func (r result) String() string { return fmt.Sprintf("%#v", r) }
+
+func run(scan *bufio.Scanner) (*result, error) {
+
+	for scan.Scan() {
+		_ = scan.Text()
+
+	}
+
+	return &result{}, nil
+}

aoc2024/day01/main_test.go

@@ -0,0 +1,41 @@
+package main
+
+import (
+	"bufio"
+	"bytes"
+	"testing"
+
+	_ "embed"
+
+	"github.com/matryer/is"
+)
+
+//go:embed example.txt
+var example []byte
+
+//go:embed input.txt
+var input []byte
+
+func TestExample(t *testing.T) {
+	is := is.New(t)
+	scan := bufio.NewScanner(bytes.NewReader(example))
+
+	result, err := run(scan)
+	is.NoErr(err)
+
+	t.Log(result)
+	is.Equal(result.valuePT1, 0)
+	is.Equal(result.valuePT2, 0)
+}
+
+func TestSolution(t *testing.T) {
+	is := is.New(t)
+	scan := bufio.NewScanner(bytes.NewReader(input))
+
+	result, err := run(scan)
+	is.NoErr(err)
+
+	t.Log(result)
+	is.Equal(result.valuePT1, 0)
+	is.Equal(result.valuePT2, 0)
+}

go.mod

@@ -1,6 +1,6 @@
 module go.sour.is/advent-of-code
 
-go 1.22.0
+go 1.23.2
 
 require (
 	github.com/matryer/is v1.4.1

hacker-rank/binary-search-tree-lowest-common-ancestor/main.go

@@ -0,0 +1,84 @@
+package main
+import (
+    "fmt"
+    "os"
+    "bufio"
+    "strings"
+    "strconv"
+)
+func main() {
+    //Enter your code here. Read input from STDIN. Print output to STDOUT
+    scanner := bufio.NewScanner(os.Stdin)
+    
+    var nodes int
+    var tree *node
+    var target [2]int
+    
+    for scanner.Scan() {
+        text := scanner.Text()
+        if nodes == 0 {
+            nodes, _ = strconv.Atoi(text)
+            continue
+        }
+        
+        if tree == nil {
+            for _, s := range strings.Fields(text) {
+                v, _ := strconv.Atoi(s)
+                tree = insertNode(tree, &node{value:v})
+            }
+            continue
+        }
+        
+        for i, s := range strings.Fields(text) {
+            v, _ := strconv.Atoi(s)
+            target[i] = v
+        }
+    }
+    if target[0]>target[1] {
+        target[0], target[1] = target[1], target[0]
+    }
+    fmt.Fprintln(os.Stderr, tree)
+    if n := lsa(tree, target); n != nil {
+        fmt.Println(n.value)
+        return
+    }
+    fmt.Println("nil")
+}
+
+type node struct{
+    value int
+    left *node
+    right *node
+}
+func insertNode(root, n *node) *node {
+    if root == nil {
+        return n
+    }
+    if root.value > n.value {
+        root.left = insertNode(root.left, n)
+        return root
+    }
+    root.right = insertNode(root.right, n)
+    return root
+}
+
+func (n *node) String() string {
+    if n == nil { return "nil" }
+    return fmt.Sprintf("%v (%v %v)", n.value, n.left, n.right)
+}
+
+func lsa(tree *node, target [2]int) *node {
+    if tree == nil {
+        return nil
+    }
+    
+    if target[0]>tree.value {
+        return lsa(tree.right, target)
+    }
+    
+    if target[1]<tree.value {
+        return lsa(tree.left, target)
+    }
+    
+    return tree
+}

hacker-rank/counting-sort/main.go

@@ -0,0 +1,80 @@
+package main
+
+import (
+    "bufio"
+    "fmt"
+    "io"
+    "os"
+    "strconv"
+    "strings"
+)
+
+/*
+ * Complete the 'countingSort' function below.
+ *
+ * The function is expected to return an INTEGER_ARRAY.
+ * The function accepts INTEGER_ARRAY arr as parameter.
+ */
+
+func countingSort(arr []int32) []int32 {
+    freq := make([]int32, 100)
+    for _, i := range arr {
+        freq[i]++
+    }
+    return freq
+}
+
+func main() {
+    reader := bufio.NewReaderSize(os.Stdin, 16 * 1024 * 1024)
+
+    stdout, err := os.Create(os.Getenv("OUTPUT_PATH"))
+    checkError(err)
+
+    defer stdout.Close()
+
+    writer := bufio.NewWriterSize(stdout, 16 * 1024 * 1024)
+
+    nTemp, err := strconv.ParseInt(strings.TrimSpace(readLine(reader)), 10, 64)
+    checkError(err)
+    n := int32(nTemp)
+
+    arrTemp := strings.Split(strings.TrimSpace(readLine(reader)), " ")
+
+    var arr []int32
+
+    for i := 0; i < int(n); i++ {
+        arrItemTemp, err := strconv.ParseInt(arrTemp[i], 10, 64)
+        checkError(err)
+        arrItem := int32(arrItemTemp)
+        arr = append(arr, arrItem)
+    }
+
+    result := countingSort(arr)
+
+    for i, resultItem := range result {
+        fmt.Fprintf(writer, "%d", resultItem)
+
+        if i != len(result) - 1 {
+            fmt.Fprintf(writer, " ")
+        }
+    }
+
+    fmt.Fprintf(writer, "\n")
+
+    writer.Flush()
+}
+
+func readLine(reader *bufio.Reader) string {
+    str, _, err := reader.ReadLine()
+    if err == io.EOF {
+        return ""
+    }
+
+    return strings.TrimRight(string(str), "\r\n")
+}
+
+func checkError(err error) {
+    if err != nil {
+        panic(err)
+    }
+}

hacker-rank/diagonal-difference/main.go

@@ -0,0 +1,84 @@
+package main
+
+import (
+    "bufio"
+    "fmt"
+    "io"
+    "os"
+    "strconv"
+    "strings"
+)
+
+/*
+ * Complete the 'diagonalDifference' function below.
+ *
+ * The function is expected to return an INTEGER.
+ * The function accepts 2D_INTEGER_ARRAY arr as parameter.
+ */
+
+func diagonalDifference(arr [][]int32) int32 {
+    var sum int32
+    for i, row := range arr {
+        sum += row[i] - row[len(row)-i-1]        
+    }
+    if sum < 0 {
+        sum *= -1
+    }
+    
+    return sum
+}
+
+func main() {
+    reader := bufio.NewReaderSize(os.Stdin, 16 * 1024 * 1024)
+
+    stdout, err := os.Create(os.Getenv("OUTPUT_PATH"))
+    checkError(err)
+
+    defer stdout.Close()
+
+    writer := bufio.NewWriterSize(stdout, 16 * 1024 * 1024)
+
+    nTemp, err := strconv.ParseInt(strings.TrimSpace(readLine(reader)), 10, 64)
+    checkError(err)
+    n := int32(nTemp)
+
+    var arr [][]int32
+    for i := 0; i < int(n); i++ {
+        arrRowTemp := strings.Split(strings.TrimRight(readLine(reader)," \t\r\n"), " ")
+
+        var arrRow []int32
+        for _, arrRowItem := range arrRowTemp {
+            arrItemTemp, err := strconv.ParseInt(arrRowItem, 10, 64)
+            checkError(err)
+            arrItem := int32(arrItemTemp)
+            arrRow = append(arrRow, arrItem)
+        }
+
+        if len(arrRow) != int(n) {
+            panic("Bad input")
+        }
+
+        arr = append(arr, arrRow)
+    }
+
+    result := diagonalDifference(arr)
+
+    fmt.Fprintf(writer, "%d\n", result)
+
+    writer.Flush()
+}
+
+func readLine(reader *bufio.Reader) string {
+    str, _, err := reader.ReadLine()
+    if err == io.EOF {
+        return ""
+    }
+
+    return strings.TrimRight(string(str), "\r\n")
+}
+
+func checkError(err error) {
+    if err != nil {
+        panic(err)
+    }
+}

hacker-rank/flipping-bits/main.go

@@ -0,0 +1,64 @@
+package main
+
+import (
+    "bufio"
+    "fmt"
+    "io"
+    "os"
+    "strconv"
+    "strings"
+)
+
+/*
+ * Complete the 'flippingBits' function below.
+ *
+ * The function is expected to return a LONG_INTEGER.
+ * The function accepts LONG_INTEGER n as parameter.
+ */
+
+func flippingBits(n int64) int64 {
+    // Write your code here
+    max := int64(^uint32(0))
+    return n ^ max
+}
+
+func main() {
+    reader := bufio.NewReaderSize(os.Stdin, 16 * 1024 * 1024)
+
+    stdout, err := os.Create(os.Getenv("OUTPUT_PATH"))
+    checkError(err)
+
+    defer stdout.Close()
+
+    writer := bufio.NewWriterSize(stdout, 16 * 1024 * 1024)
+
+    qTemp, err := strconv.ParseInt(strings.TrimSpace(readLine(reader)), 10, 64)
+    checkError(err)
+    q := int32(qTemp)
+
+    for qItr := 0; qItr < int(q); qItr++ {
+        n, err := strconv.ParseInt(strings.TrimSpace(readLine(reader)), 10, 64)
+        checkError(err)
+
+        result := flippingBits(n)
+
+        fmt.Fprintf(writer, "%d\n", result)
+    }
+
+    writer.Flush()
+}
+
+func readLine(reader *bufio.Reader) string {
+    str, _, err := reader.ReadLine()
+    if err == io.EOF {
+        return ""
+    }
+
+    return strings.TrimRight(string(str), "\r\n")
+}
+
+func checkError(err error) {
+    if err != nil {
+        panic(err)
+    }
+}