Merge pull request #128 from asphaltbuffet/2024-02

2024 02

exercises/2024/02-red-NosedReports/README.md

@@ -0,0 +1,37 @@
+# [Day 2: Red-Nosed Reports](https://adventofcode.com/2024/day/2)
+
+<!-- These are helper text to make formatting the yearly readme consistent and easier...
+
+[Day 2: Red-Nosed Reports][rm2]
+[Go][go2]
+[Python][py2]
+
+[rm2]: 02-red-NosedReports/README.md
+[go2]: 02-red-NosedReports/go
+[py2]: 02-red-NosedReports/py
+
+-->
+
+## Go
+
+```text
+──────────────────────────────────────────
+           ADVENT OF CODE 2024            
+         Day 2: Red-Nosed Reports         
+──────────────────────────────────────────
+Solving (Go)...
+  1.1: PASS                478µs
+      ⤷ 549
+  2.1: PASS                707µs
+      ⤷ 589
+```
+
+## Python
+
+```text
+< section intentionally left blank >
+```
+
+## 2024 Run Times
+
+![2024 exercise run-time graphs](../run-times.png)

exercises/2024/02-red-NosedReports/go/exercise.go

@@ -0,0 +1,54 @@
+package exercises
+
+import (
+	"github.com/asphaltbuffet/advent-of-code/internal/common"
+)
+
+// Exercise for Advent of Code 2024 day 2.
+type Exercise struct {
+	common.BaseExercise
+}
+
+// One returns the answer to the first part of the exercise.
+func (e Exercise) One(instr string) (any, error) {
+	reports, err := parse(instr)
+	if err != nil {
+		return nil, err
+	}
+
+	var count int
+	for _, r := range reports {
+		if ok := r.isSafe(); ok {
+			count++
+		}
+	}
+
+	return count, nil
+}
+
+// Two returns the answer to the second part of the exercise.
+func (e Exercise) Two(instr string) (any, error) {
+	reports, err := parse(instr)
+	if err != nil {
+		return nil, err
+	}
+
+	var count int
+	for _, r := range reports {
+		r := r
+		if ok := r.isSafe(); ok {
+			count++
+		} else {
+			for i := 0; i < len(r.values); i++ {
+				tmp := Report{values: removeAt(r.values, i)}
+
+				if altOk := tmp.isSafe(); altOk {
+					count++
+					break
+				}
+			}
+		}
+	}
+
+	return count, nil
+}

exercises/2024/02-red-NosedReports/go/reports.go

@@ -0,0 +1,72 @@
+package exercises
+
+import (
+	"fmt"
+	"strconv"
+	"strings"
+)
+
+type Report struct {
+	values []int
+}
+
+func parse(s string) ([]Report, error) {
+	var reports []Report
+
+	for _, line := range strings.Split(s, "\n") {
+		vals := strings.Fields(line)
+		r := Report{
+			values: make([]int, 0, len(vals)),
+		}
+
+		for i, level := range vals {
+			v, err := strconv.Atoi(level)
+			if err != nil {
+				return nil, fmt.Errorf("failed to parse line %d: %w", i, err)
+			}
+
+			r.values = append(r.values, v)
+		}
+		reports = append(reports, r)
+
+	}
+
+	return reports, nil
+}
+
+func (r *Report) isSafe() bool {
+	if r.values[0] < r.values[1] {
+		for i, j := 0, 1; j < len(r.values); i, j = i+1, j+1 {
+			if r.values[j]-r.values[i] < 1 || r.values[j]-r.values[i] > 3 {
+				return false
+			}
+		}
+	} else {
+		for i, j := 0, 1; j < len(r.values); i, j = i+1, j+1 {
+			if r.values[i]-r.values[j] < 1 || r.values[i]-r.values[j] > 3 {
+				return false
+			}
+		}
+	}
+
+	return true
+}
+
+func makeSafe(r *Report, idx int) (int, bool) {
+	fmt.Println(r.values)
+	for i := 0; i < len(r.values); i++ {
+		tmp := make([]int, 0, len(r.values)-1)
+		tmp = append(tmp, r.values[:i]...)
+		tmp = append(tmp, r.values[i+1:]...)
+
+		fmt.Println(tmp)
+	}
+	return -1, true
+}
+
+func removeAt(r []int, idx int) []int {
+	tmp := make([]int, len(r))
+	copy(tmp, r)
+	tmp = append(tmp[:idx], tmp[idx+1:]...)
+	return tmp
+}

exercises/2024/02-red-NosedReports/go/reports_test.go

@@ -0,0 +1,107 @@
+package exercises
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestReport_isSafe(t *testing.T) {
+	tests := []struct {
+		name      string
+		values    []int
+		assertion assert.BoolAssertionFunc
+	}{
+		{"example 1", []int{7, 6, 4, 2, 1}, assert.True},
+		{"example 2", []int{1, 2, 7, 8, 9}, assert.False},
+		{"example 3", []int{9, 7, 6, 2, 1}, assert.False},
+		{"example 4", []int{1, 3, 2, 4, 5}, assert.False},
+		{"example 5", []int{8, 6, 4, 4, 1}, assert.False},
+		{"example 6", []int{1, 3, 6, 7, 9}, assert.True},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			r := &Report{values: tt.values}
+
+			tt.assertion(t, r.isSafe())
+		})
+	}
+}
+
+func Test_parse(t *testing.T) {
+	tests := []struct {
+		name      string
+		s         string
+		want      []Report
+		assertion assert.ErrorAssertionFunc
+	}{
+		{
+			name: "example all",
+			s:    "7 6 4 2 1\n1 2 7 8 9\n9 7 6 2 1\n1 3 2 4 5\n8 6 4 4 1\n1 3 6 7 9",
+			want: []Report{
+				{
+					values: []int{7, 6, 4, 2, 1},
+				},
+				{
+					values: []int{1, 2, 7, 8, 9},
+				},
+				{
+					values: []int{9, 7, 6, 2, 1},
+				},
+				{
+					values: []int{1, 3, 2, 4, 5},
+				},
+				{
+					values: []int{8, 6, 4, 4, 1},
+				},
+				{
+					values: []int{1, 3, 6, 7, 9},
+				},
+			},
+			assertion: assert.NoError,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got, err := parse(tt.s)
+			tt.assertion(t, err)
+			assert.Equal(t, tt.want, got)
+		})
+	}
+}
+
+func Test_removeAt(t *testing.T) {
+	type args struct {
+		r   []int
+		idx int
+	}
+	tests := []struct {
+		name string
+		args args
+		want []int
+	}{
+		{
+			name: "first",
+			args: args{
+				r:   []int{1, 2, 3},
+				idx: 0,
+			},
+			want: []int{2, 3},
+		},
+		{
+			name: "last",
+			args: args{
+				r:   []int{1, 2, 3},
+				idx: 2,
+			},
+			want: []int{1, 2},
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got := removeAt(tt.args.r, tt.args.idx)
+			assert.Len(t, got, len(tt.want))
+			// assert.Equal(t, tt.want, removeAt(tt.args.r, tt.args.idx))
+		})
+	}
+}

exercises/2024/02-red-NosedReports/info.json

@@ -0,0 +1,28 @@
+{
+  "id": "2024-02",
+  "title": "Red-Nosed Reports",
+  "year": 2024,
+  "day": 2,
+  "url": "https://adventofcode.com/2024/day/2",
+  "data": {
+    "inputFile": "input.txt",
+    "testCases": {
+      "one": [
+        {
+          "input": "7 6 4 2 1\n1 2 7 8 9\n9 7 6 2 1\n1 3 2 4 5\n8 6 4 4 1\n1 3 6 7 9",
+          "expected": "2"
+        }
+      ],
+      "two": [
+        {
+          "input": "7 6 4 2 1\n1 2 7 8 9\n9 7 6 2 1\n1 3 2 4 5\n8 6 4 4 1\n1 3 6 7 9",
+          "expected": "4"
+        }
+      ]
+    },
+    "answers": {
+      "a": "549",
+      "b": "589"
+    }
+  }
+}

exercises/2024/README.md

@@ -6,8 +6,8 @@
 
 | Title                            | Stars | Solutions |
 | -------------------------------- | :---: | --------- |
-| [Day 1: Historian Hysteria][rm1] |  ★★   | [Go][go1] |
-| Day 2                            |  ☆☆   |           |
+| [Day 1: Historian Hysteria][rm1] |  ⭐⭐   | [Go][go1] |
+| [Day 2: Red-Nosed Reports][rm2]  |  ⭐⭐   | [Go][go2] |
 | Day 3                            |  ☆☆   |           |
 | Day 4                            |  ☆☆   |           |
 | Day 5                            |  ☆☆   |           |
@@ -46,3 +46,5 @@ TODO
 
 [rm1]: 01-historianHysteria/README.md
 [go1]: 01-historianHysteria/go
+[rm2]: 02-red-NosedReports/README.md
+[go2]: 02-red-NosedReports/go