2025 Day 5 Complete!

2025/day05/main.go

@@ -0,0 +1,111 @@
+package main
+
+import (
+	"fmt"
+	"os"
+
+	h "git.bullercodeworks.com/brian/adventofcode/helpers"
+)
+
+func main() {
+	inp := h.StdinToStringSlice()
+	part1(inp)
+	fmt.Println()
+	part2(inp)
+}
+
+func part1(inp []string) {
+	var ret int
+	fresh, ing := parseDB(inp)
+	for i := range ing {
+		for j := range fresh {
+			if fresh[j].Contains(ing[i]) {
+				ret++
+				break
+			}
+		}
+	}
+	fmt.Println("# Part 1")
+	fmt.Println(ret)
+}
+
+func part2(inp []string) {
+	fresh, _ := parseDB(inp)
+	for {
+		var toDel []*Range
+		for i := 0; i < len(fresh)-1; i++ {
+			for j := i + 1; j < len(fresh); j++ {
+				if fresh[i].Overlaps(fresh[j]) {
+					fresh[i].Merge(fresh[j])
+					toDel = append(toDel, fresh[j])
+				}
+			}
+			if len(toDel) > 0 {
+				break
+			}
+		}
+		if len(toDel) == 0 {
+			break
+		}
+		for i := range toDel {
+			for j := 0; j < len(fresh); j++ {
+				if fresh[j] == toDel[i] {
+					fresh = append(fresh[:j], fresh[j+1:]...)
+					break
+				}
+			}
+		}
+	}
+
+	// At this point, all ranges in 'fresh' should be non-overlapping
+	var ret int
+	for i := range fresh {
+		ret += fresh[i].Size()
+	}
+	fmt.Println("# Part 2")
+	fmt.Println(ret)
+}
+
+type Range struct {
+	beg, end int
+}
+
+func NewRange(inp string) *Range {
+	r := Range{}
+	fmt.Sscanf(inp, "%d-%d", &r.beg, &r.end)
+	return &r
+}
+func (r *Range) Contains(i int) bool { return r.beg <= i && i <= r.end }
+func (r *Range) Overlaps(r2 *Range) bool {
+	return r.Contains(r2.beg) || r.Contains(r2.end) || r2.Contains(r.beg) || r2.Contains(r.end)
+}
+func (r *Range) Merge(r2 *Range) {
+	if !r.Overlaps(r2) {
+		fmt.Println("Panic! Tried to merge non-overlapping ranges")
+		os.Exit(1)
+	}
+	r.beg = h.Min(r.beg, r2.beg)
+	r.end = h.Max(r.end, r2.end)
+}
+func (r *Range) Size() int     { return (r.end - r.beg) + 1 }
+func (r Range) String() string { return fmt.Sprintf("%d to %d", r.beg, r.end) }
+
+func parseDB(inp []string) ([]*Range, []int) {
+	var retRng []*Range
+	var retInt []int
+	inRanges := true
+	for i := range inp {
+		if inp[i] == "" {
+			inRanges = false
+			continue
+		}
+		if inRanges {
+			retRng = append(retRng, NewRange(inp[i]))
+			continue
+		}
+		var ri int
+		fmt.Sscanf(inp[i], "%d", &ri)
+		retInt = append(retInt, ri)
+	}
+	return retRng, retInt
+}

2025/day05/problem

@@ -0,0 +1,114 @@
+Advent of Code
+   br0xen [7](AoC++) 10*
+
+--- Day 5: Cafeteria ---
+
+   As the forklifts break through the wall, the Elves are delighted to
+   discover that there was a cafeteria on the other side after all.
+
+   You can hear a commotion coming from the kitchen. "At this rate, we won't
+   have any time left to put the wreaths up in the dining hall!" Resolute in
+   your quest, you investigate.
+
+   "If only we hadn't switched to the new inventory management system right
+   before Christmas!" another Elf exclaims. You ask what's going on.
+
+   The Elves in the kitchen explain the situation: because of their
+   complicated new inventory management system, they can't figure out which
+   of their ingredients are fresh and which are spoiled. When you ask how it
+   works, they give you a copy of their database (your puzzle input).
+
+   The database operates on ingredient IDs. It consists of a list of fresh
+   ingredient ID ranges, a blank line, and a list of available ingredient
+   IDs. For example:
+
+ 3-5
+ 10-14
+ 16-20
+ 12-18
+
+ 1
+ 5
+ 8
+ 11
+ 17
+ 32
+
+   The fresh ID ranges are inclusive: the range 3-5 means that ingredient IDs
+   3, 4, and 5 are all fresh. The ranges can also overlap; an ingredient ID
+   is fresh if it is in any range.
+
+   The Elves are trying to determine which of the available ingredient IDs
+   are fresh. In this example, this is done as follows:
+
+     • Ingredient ID 1 is spoiled because it does not fall into any range.
+     • Ingredient ID 5 is fresh because it falls into range 3-5.
+     • Ingredient ID 8 is spoiled.
+     • Ingredient ID 11 is fresh because it falls into range 10-14.
+     • Ingredient ID 17 is fresh because it falls into range 16-20 as well as
+       range 12-18.
+     • Ingredient ID 32 is spoiled.
+
+   So, in this example, 3 of the available ingredient IDs are fresh.
+
+   Process the database file from the new inventory management system. How
+   many of the available ingredient IDs are fresh?
+
+   Your puzzle answer was 848.
+
+--- Part Two ---
+
+   The Elves start bringing their spoiled inventory to the trash chute at the
+   back of the kitchen.
+
+   So that they can stop bugging you when they get new inventory, the Elves
+   would like to know all of the IDs that the fresh ingredient ID ranges
+   consider to be fresh. An ingredient ID is still considered fresh if it is
+   in any range.
+
+   Now, the second section of the database (the available ingredient IDs) is
+   irrelevant. Here are the fresh ingredient ID ranges from the above
+   example:
+
+ 3-5
+ 10-14
+ 16-20
+ 12-18
+
+   The ingredient IDs that these ranges consider to be fresh are 3, 4, 5, 10,
+   11, 12, 13, 14, 15, 16, 17, 18, 19, and 20. So, in this example, the fresh
+   ingredient ID ranges consider a total of 14 ingredient IDs to be fresh.
+
+   Process the database file again. How many ingredient IDs are considered to
+   be fresh according to the fresh ingredient ID ranges?
+
+   Your puzzle answer was 334714395325710.
+
+   Both parts of this puzzle are complete! They provide two gold stars: **
+
+   At this point, you should [16]return to your Advent calendar and try
+   another puzzle.
+
+   If you still want to see it, you can [17]get your puzzle input.
+
+References
+
+   Visible links
+   1. https://adventofcode.com/
+   2. https://adventofcode.com/2025/about
+   3. https://adventofcode.com/2025/events
+   4. https://adventofcode.com/2025/shop
+   5. https://adventofcode.com/2025/settings
+   6. https://adventofcode.com/2025/auth/logout
+   7. Advent of Code Supporter
+	https://adventofcode.com/2025/support
+   8. https://adventofcode.com/2025
+   9. https://adventofcode.com/2025
+  10. https://adventofcode.com/2025/support
+  11. https://adventofcode.com/2025/sponsors
+  12. https://adventofcode.com/2025/leaderboard/private
+  13. https://adventofcode.com/2025/stats
+  14. https://adventofcode.com/2025/sponsors
+  15. https://adventofcode.com/2025/sponsors/redirect?url=https%3A%2F%2Fwww%2Eonechronos%2Ecom
+  16. https://adventofcode.com/2025
+  17. https://adventofcode.com/2025/day/5/input

2025/day05/testinput

@@ -0,0 +1,11 @@
+ 3-5
+ 10-14
+ 16-20
+ 12-18
+
+ 1
+ 5
+ 8
+ 11
+ 17
+ 32