2017 Complete!

2017/day24/day24.go

@@ -10,106 +10,56 @@ import (
 )
 
 var comps []Component
+var strongest, best Bridge
 
-// Greater than 907
 func main() {
 	inp := StdinToStrings()
 	for i := range inp {
 		comps = append(comps, NewComponent(inp[i]))
 	}
 
-	// Need to build chains of all permutations
-	var perms []Bridge
-	for i := range comps {
-		if comps[i].Has(0) {
-			perms = append(perms, Bridge([]Component{comps[i]}))
-		}
-	}
+	FindStrongest([]Component{NewComponent("0/0")})
+	fmt.Println("Strongest:\n", strongest)
 
-	changed := true
-	for changed {
-		perms, changed = GetNextPerms(perms)
-	}
-
-	var highB Bridge
-	highest := 0
-	for _, b := range perms {
-		if b.Value() > highest {
-			highB = b
-			highest = b.Value()
-		}
-	}
-	fmt.Println(highB)
-	/*
-		for _, b := range perms {
-			tst := GetAllThatFit(b)
-			for i := range tst {
-
-			}
-
-			for tst != nil {
-				b = b.Add(*tst)
-				tst = GetNextBest(b)
-			}
-			fmt.Println(b)
-		}
-	*/
+	FindBest([]Component{NewComponent("0/0")})
+	fmt.Println("Best:\n", best)
 }
 
-func GetNextPerms(perms []Bridge) ([]Bridge, bool) {
-	var ret []Bridge
-	var changed bool
-	for i := range perms {
-		if !perms[i].IsDone() {
-			allComps := GetAllThatFit(perms[i])
-			if len(allComps) == 0 {
-				ret = append(ret, perms[i].Add(NewComponent("0/0")))
-			}
-			for j := range allComps {
-				ret = append(ret, perms[i].Add(allComps[j]))
-				changed = true
-			}
+// Strongest, regardless of length
+func FindStrongest(bridge Bridge) {
+	if bridge.Strength() > strongest.Strength() {
+		strongest = bridge
+	}
+	for i := range comps {
+		if comps[i].Has(bridge.Needs()) && !bridge.Has(comps[i]) {
+			FindStrongest(append(bridge, comps[i]))
 		}
 	}
-	return ret, changed
 }
 
-func GetAllThatFit(b Bridge) []Component {
-	var ret []Component
-	port := b.Needs()
-	for i := range comps {
-		if comps[i].Has(port) && !b.Has(comps[i]) {
-			ret = append(ret, comps[i])
+// Longest and Strongest
+func FindBest(bridge Bridge) {
+	if bridge.Length() > best.Length() {
+		best = append([]Component{}, bridge...)
+	} else if bridge.Length() == best.Length() {
+		if bridge.Strength() > best.Strength() {
+			best = bridge
 		}
 	}
-	return ret
-}
 
-func GetNextBest(b Bridge) *Component {
-	var best *Component
-	port := b.Needs()
 	for i := range comps {
-		if comps[i].Has(port) && !b.Has(comps[i]) {
-			if best == nil || comps[i].Value() > best.Value() {
-				best = &comps[i]
-			}
+		if comps[i].Has(bridge.Needs()) && !bridge.Has(comps[i]) {
+			FindBest(append(bridge, comps[i]))
 		}
 	}
-	return best
 }
 
 type Bridge []Component
 
-func (b Bridge) IsDone() bool {
-	t := []Component(b)
-	c := t[len(t)-1]
-	return c.Value() == 0
-}
-
-func (b Bridge) Value() int {
+func (b Bridge) Strength() int {
 	var ret int
 	for _, v := range []Component(b) {
-		ret += v.Value()
+		ret += v.Strength()
 	}
 	return ret
 }
@@ -143,12 +93,16 @@ func (b Bridge) Needs() int {
 	return c.Other(c1.Side2)
 }
 
+func (b Bridge) Length() int {
+	return len([]Component(b))
+}
+
 func (b Bridge) String() string {
 	ret := "[ "
 	for _, v := range []Component(b) {
 		ret += v.Name + " "
 	}
-	return fmt.Sprint(ret+"] ", b.Value())
+	return fmt.Sprint(ret+"(", b.Strength(), ";", b.Length(), ") ]")
 }
 
 type Component struct {
@@ -169,7 +123,7 @@ func (c *Component) Equals(t Component) bool {
 	return c.Side1 == t.Side1 && c.Side2 == t.Side2
 }
 
-func (c *Component) Value() int {
+func (c *Component) Strength() int {
 	return c.Side1 + c.Side2
 }
 
@@ -184,6 +138,10 @@ func (c *Component) Other(v int) int {
 	return c.Side1
 }
 
+func (c *Component) String() string {
+	return c.Name
+}
+
 func Atoi(i string) int {
 	var ret int
 	var err error