Added solutions for 14th day: Extended Polymerization

4 files changed, 312 insertions, 0 deletions

diff --git a/2021/14/example b/2021/14/example
new file mode 100644
index 0000000..b5594dd
--- /dev/null
+++ b/2021/14/example
@@ -0,0 +1,18 @@
+NNCB
+
+CH -> B
+HH -> N
+CB -> H
+NH -> C
+HB -> C
+HC -> B
+HN -> C
+NN -> C
+BH -> H
+NC -> B
+NB -> B
+BN -> B
+BB -> N
+BC -> B
+CC -> N
+CN -> C
diff --git a/2021/14/first.go b/2021/14/first.go
new file mode 100644
index 0000000..e6256ac
--- /dev/null
+++ b/2021/14/first.go
@@ -0,0 +1,94 @@
+package main
+
+import (
+	"bufio"
+	"fmt"
+	"os"
+	"sort"
+	"strings"
+)
+
+type transform struct {
+	first  byte
+	second byte
+	res    byte
+	count  int
+}
+
+type letter struct {
+	value byte
+	count int
+}
+
+var (
+	pairs   []transform
+	letters []letter
+)
+
+func main() {
+	scanner := bufio.NewScanner(os.Stdin)
+
+	scanner.Scan()
+	polymer := scanner.Text()
+out:
+	for i := 0; i < len(polymer); i++ {
+		for j := range letters {
+			if letters[j].value == polymer[i] {
+				letters[j].count++
+				continue out
+			}
+		}
+		letters = append(letters, letter{polymer[i], 1})
+	}
+	scanner.Scan()
+
+	for scanner.Scan() {
+		line := strings.Split(scanner.Text(), " -> ")
+		pairs = append(pairs, transform{line[0][0], line[0][1], line[1][0], 0})
+	}
+	for i := 0; i < len(polymer)-1; i++ {
+		for j, v := range pairs {
+			if v.first == polymer[i] && v.second == polymer[i+1] {
+				pairs[j].count++
+			}
+		}
+	}
+	newPairs := make([]transform, len(pairs))
+	copy(newPairs, pairs)
+	for s := 1; s < 10; s++ {
+		for j := range newPairs {
+			newPairs[j].count = 0
+		}
+		for _, a := range pairs {
+			if a.count > 0 {
+				for j, b := range pairs {
+					if b.first == a.first && b.second == a.res {
+						newPairs[j].count += a.count
+						break
+					}
+				}
+				for j, b := range pairs {
+					if b.first == a.res && b.second == a.second {
+						newPairs[j].count += a.count
+						break
+					}
+				}
+			}
+		}
+		copy(pairs, newPairs)
+	out2:
+		for _, v := range pairs {
+			for j := range letters {
+				if letters[j].value == v.res {
+					letters[j].count += v.count
+					continue out2
+				}
+			}
+			letters = append(letters, letter{v.res, v.count})
+		}
+	}
+	sort.Slice(letters, func(i, j int) bool {
+		return letters[i].count < letters[j].count
+	})
+	fmt.Println(letters[len(letters)-1].count - letters[0].count)
+}
diff --git a/2021/14/input b/2021/14/input
new file mode 100644
index 0000000..331c91b
--- /dev/null
+++ b/2021/14/input
@@ -0,0 +1,102 @@
+ONSVVHNCFVBHKVPCHCPV
+
+VO -> C
+VV -> S
+HK -> H
+FC -> C
+VB -> V
+NO -> H
+BN -> B
+FP -> K
+CS -> C
+HC -> S
+FS -> K
+KH -> V
+CH -> H
+BP -> K
+OF -> K
+SS -> F
+SP -> C
+PN -> O
+CK -> K
+KS -> H
+HO -> K
+FV -> F
+SN -> P
+HN -> O
+KK -> H
+KP -> O
+CN -> N
+BO -> C
+CC -> H
+PB -> F
+PV -> K
+BV -> K
+PP -> H
+KB -> F
+NC -> F
+PC -> V
+FN -> N
+NH -> B
+CF -> V
+PO -> F
+KC -> S
+VP -> P
+HH -> N
+OB -> O
+KN -> O
+PS -> N
+SF -> V
+VK -> F
+CO -> N
+KF -> B
+VC -> C
+SH -> S
+HV -> V
+FK -> O
+NV -> N
+SC -> O
+BK -> F
+BB -> K
+HF -> K
+OC -> O
+KO -> V
+OS -> P
+FF -> O
+PH -> F
+FB -> O
+NN -> C
+NK -> C
+HP -> B
+PF -> H
+PK -> C
+NP -> O
+NS -> V
+CV -> O
+VH -> C
+OP -> N
+SO -> O
+SK -> H
+SV -> O
+NF -> H
+BS -> K
+BH -> O
+VN -> S
+HB -> O
+OH -> K
+CB -> B
+BC -> S
+OV -> F
+BF -> P
+OO -> F
+HS -> H
+ON -> P
+NB -> F
+CP -> S
+SB -> V
+VF -> C
+OK -> O
+FH -> H
+KV -> S
+FO -> C
+VS -> B
diff --git a/2021/14/second.go b/2021/14/second.go
new file mode 100644
index 0000000..06c6890
--- /dev/null
+++ b/2021/14/second.go
@@ -0,0 +1,98 @@
+package main
+
+// TODO Off by one! I don't know where!!!!!
+// I get  : 3459174981022
+// I need : 3459174981021
+
+import (
+	"bufio"
+	"fmt"
+	"os"
+	"sort"
+	"strings"
+)
+
+type transform struct {
+	first  byte
+	second byte
+	res    byte
+	count  int
+}
+
+type letter struct {
+	value byte
+	count int
+}
+
+var (
+	pairs   []transform
+	letters []letter
+)
+
+func main() {
+	scanner := bufio.NewScanner(os.Stdin)
+
+	scanner.Scan()
+	polymer := scanner.Text()
+out:
+	for i := 0; i < len(polymer); i++ {
+		for j := range letters {
+			if letters[j].value == polymer[i] {
+				letters[j].count++
+				continue out
+			}
+		}
+		letters = append(letters, letter{polymer[i], 1})
+	}
+	scanner.Scan()
+
+	for scanner.Scan() {
+		line := strings.Split(scanner.Text(), " -> ")
+		pairs = append(pairs, transform{line[0][0], line[0][1], line[1][0], 0})
+	}
+	for i := 0; i < len(polymer)-1; i++ {
+		for j, v := range pairs {
+			if v.first == polymer[i] && v.second == polymer[i+1] {
+				pairs[j].count++
+			}
+		}
+	}
+	newPairs := make([]transform, len(pairs))
+	copy(newPairs, pairs)
+	for s := 1; s < 40; s++ {
+		for j := range newPairs {
+			newPairs[j].count = 0
+		}
+		for _, a := range pairs {
+			if a.count > 0 {
+				for j, b := range pairs {
+					if b.first == a.first && b.second == a.res {
+						newPairs[j].count += a.count
+						break
+					}
+				}
+				for j, b := range pairs {
+					if b.first == a.res && b.second == a.second {
+						newPairs[j].count += a.count
+						break
+					}
+				}
+			}
+		}
+		copy(pairs, newPairs)
+	out2:
+		for _, v := range pairs {
+			for j := range letters {
+				if letters[j].value == v.res {
+					letters[j].count += v.count
+					continue out2
+				}
+			}
+			letters = append(letters, letter{v.res, v.count})
+		}
+	}
+	sort.Slice(letters, func(i, j int) bool {
+		return letters[i].count < letters[j].count
+	})
+	fmt.Println(letters[len(letters)-1].count - letters[0].count)
+}