1 files changed, 22 insertions, 1 deletions
diff --git a/aoc23/util.go b/aoc23/util.go
index 414756a..097f413 100644
--- a/aoc23/util.go
+++ b/aoc23/util.go
@@ -4,6 +4,7 @@ import (
 	"bufio"
 	"fmt"
 	"io"
+	"math"
 	"os"
 	"strconv"
 	"strings"
@@ -23,6 +24,16 @@ func (s *Set[V]) Add(v V) bool {
 	return !ok
 }
 
+func (s *Set[V]) AddAll(vs []V) bool {
+	changed := false
+	for _, v := range vs {
+		if s.Add(v) {
+			changed = true
+		}
+	}
+	return changed
+}
+
 func (s *Set[V]) Contains(v V) bool {
 	_, ok := s.set[v]
 	return ok
@@ -112,6 +123,8 @@ func add(a, b int) int { return a + b }
 
 func mul(a, b int) int { return a * b }
 
+func pow(a, b int) int { return int(math.Pow(float64(a), float64(b))) }
+
 func reduce[V any](values []V, f func(a, b V) V, initial V) V {
 	acc := initial
 	for _, v := range values {
@@ -138,7 +151,15 @@ func filter[V any](values []V, pred func(v V) bool) []V {
 	return filtered
 }
 
-func frequency[V any](values []V, pred func(v V) bool) int { return len(filter(values, pred)) }
+func frequency[V any](values []V, pred func(v V) bool) int {
+	n := 0
+	for _, v := range values {
+		if pred(v) {
+			n++
+		}
+	}
+	return n
+}
 
 func anyMatch[V any](values []V, pred func(v V) bool) bool { return frequency(values, pred) > 0 }